This video saved me a lot of time and probably money trying to find the reason my car was slow and not boosting. I looked at the small black part of the hose and indeed it was split just before the fitting on the intake manifold. My metal fitting was also totally blocked and I used a tiny drill bit to completely clean it. Followed your procedure and now the car runs so much better. Transmission shifts are still not smooth but that problem is further down the vacuum system and I now think I know enough to try and fix it - THANK YOU!
First make sure that your engine vacuum is ok. Most of the time it is the vacuum activated transmission modulator. It is adjustable by removing the plastic cover and turning the adjustment counterclockwise to soften the shifts. The modulator is located in the driver side (left) of the transmission. There is a vacuum line leading to it. Make sure it is tight and not leaking. Do not make big adjustments to your modulator. Do this in small increments. Most of the time, only a few degrees will be enough to change the shifting behavior.
Hello Ralph I know I’m driving you crazy I have to ask you one last question I think that valve stays open in fact I know it stays open I did not put the lids on it but I had my son turn the switch back-and-forth no clicking that connects to my intake and the pump the transmission is not jerking only when the car is cold it gives you that little jerk head shift when it warms up smooth does that have anything to do with my turbo or overboost or under boost would it be better to stay closed or open I know I need a new one but if you can specifically tell me the most important thing that thing does I noticed another one next to the blue flying saucer and I don’t know what that one does and if it’s working Please let me know thank you Ralph thumbs up wish you were here in Michigan you’re a genius One more thing when the key is in the ignition does it always stay in the close Position when does that open when you give it gas or it stays closed thank you
The solenoid closes only when there is too much boost pressure. That is why it does not "click" when you turn the ignition on and it does not close even with the engine running at idle or normal load. This is the reason why you should check the condition occasionally to make sure that there is no oil and soot plugging it because that causes low power and rough shifting. The blue "saucer" is the vacuum amplifier. They can go bad, but that would not be my first step in troubleshooting your cold rough shift issue. The 722.3 tranny does tend to have a one or more rough shifts that go away. Assuming you got all vacuum leaks addressed (and I can not overstate how important a good vacuum level is) I would focus your attention on the rubber mushroom cap of the vacuum modulator valve at the tranny. That cap dry rots and replacing it may already cure your issue. Also, under that cap is a dial that you can make an adjustment with by turning it a click to the left or right. That would not be my first thing to check. First thing would be checking tranny fluid level and condition. Change it including draining the torque converter as well as the oil filter and pan gasket. Good luck.
Hello Ralph love your videos keep them coming need to ask you a question about my actuator on my turbo I drove the car around let it heat up good and gave it some high Revolutions I did not see the actuator move at all could you please help thank you sir I think it is seized from all the stuff inside anyway to clean that without taking everything apart I’m just not good at that any suggestions please thank you
I cannot move the Rod that connects to the waist gate I was thinking of spray intake cleaner I don’t know if it’s it’s all caked up or frozen but it is not moving at all to relieve the turbo From too much pressure I tried to move it but it’s just stuck
@@abrahamghannam2137 Well, if it is stuck it would most likely be in the "closed" position. With that being the case you would have plenty of boost and the overload protection relay valve should get a work out. Test the boost pressure with a 15psi pressure gauge in gear three at 4000rpm at the three different locations. You should have around 13 to 14.25psi there. If the overload valve is working, the white vacuum plastic hoses and connectors are ok, and the boost pressure control valve to compressor housing is ok then its time for a new to you turbo. That is about as far as I can help.
Hi, is it normal for w126- when I back up the sloped driveway and I let go of the accelerator my 560 sel will roll forward despite the fact that it is in R gear. Transmission changes gears flawlessly not grinding or anything but I find it weird that it rolls forward when in reverse- all by other (automatic tranny) cars would just stay in place. Btw- your videos did help me to worth things out thus I’m subscribing. Thanks
Hi Bobby. I believe you have the OM602 engine with either the 4G Tronic 4 speed or the 5 speed 722.5 transmission in your car. That is quite a different set up and there should not be a valve in the video on your car.
I think my switch is bad on my 1987 SDL I noticed another one under the blue flying saucer or next to it the guy that I bought the car from had all the hoses rigged I tried to put everything back the right way I don’t know the exact routing of the vacuum tried looking online and can’t find anything right if that switch is bad what kind of damage would that do to the car or engine does that lower my boost I don’t feel any suction from neither if you can show me the vacuum routing hose to the engine or pictures I’ve been looking online can’t find anything I know you’re a boss at this I seen all your work you kick everybody’s ass please help thank you sir I’ll be waiting for your response
Hi there. That sounds like a mess. Make absolutely sure that you sniff out your vacuum leaks and that the hoses and vac pods are in the correct spot. Here is the 1987 vac diagram: www.benzworld.org/cdn-cgi/image/format=auto,onerror=redirect,width=1920,height=1920,fit=scale-down/i323.photobucket.com/albums/nn447/Jeremy5848/1987%20Mercedes%20300D/Vacuum603.jpg That should help sort out the vac line routing. Good luck.
Hi, its a very nice video! But i have a question for you, i've got my own '91 w124 230e Automatic and when i put the transmission gear from P to D it feels so rough and makes the car a little bit shaky and also makes the rpm drop to 600 rpm from 700/800. But in the other hand, the gear shifting is normal when the car is running from 2nd gear, to 3rd gear and so on. Thanks.
That is most likely the tranny's shift modulator. Located on the driver's side. It does have some adjustment on top, but most likely you are better off going with a new one. Good luck.
Somebody said I could take the actuator rod off put some PB blaster on there and try to free the actuator gate open but I have one of those bubbles like a catalytic converter that’s hiding everything and the screws are almost impossible to get to any suggestions getting plenty of boost in fact too much boost If I can free that Rod everything will be OK just getting to it
Well, that "bubble" is the so called trap oxidizer. There was a service campaign from Benz that had dealers replace this part with a straight piece of cast iron pipe. The trap oxidizer used to fail on people losing power to the point of turbo/ engine failure. I doubt you will be able to get that done for free +30 years later, but you can at least try getting rid of this thing as soon as possible. This very part may be the cause of your trouble. Here is a post (of many) concerning this part. mercedesforum.com/forum/diesel-discussions-33/trap-oxidizer-replacement-24842/
Hi Ralph I got one problem I don’t wanna bother you no more I need to ask you one last question the hard line coming from the fuel injection pump valve yes birding diesel fuel right from the top of where it sits inside The nozzle on the pump I can wiggle the hard line coming from the pump no matter how much I tighten it I had change the copper crush washers and the rubber O-rings was good till today I can move that hard line and I will be sporting diesel in the car is running I don’t know where to get the hardlinesAnd is it the hard line
I think you are talking about the hard plastic lines. ECS may be able to help you: www.ecstuning.com/b-genuine-mercedes-benz-parts/fuel-hose/6150700632/
Hello stray went to check the pressure switch pulled the rubber hose off the top of the manifold put a needle inside and pulled out a bunch of garbage sludge just on the tip of the needle I cannot imagine on the inside of the intake what it looks like blew through the pressure switch free did not check it with ignition I have to really push down on the gas pedal or should I say diesel on my STL before the turbo spool’s up and it’ll jump and go you will see a lot of smoke when I jump on it seems like it is choking if I drive like an old man car drives good but when I have to go I have to push the pedal all the way down to hit that passing Geer then the turbo kick in a lot of black smoke I think my intake is just plugged up with crap any suggestions they told me to take out the intake and clean it it looks like a huge job I hope it is not my turbo I can hear it’s cooling up nicely and then winding down there is a crack in a little flex pipe that’s on the manifold right next to My EGR they said I would have to disassemble everything to replace that little bracket which cost eight bucks please help thanks
There is a lot to answer to in here. First of all, yes it is that oil and soot mixture that can plug up the fitting, hose, and the solenoid valve. Give that a good cleaning. You may want to install a good size fuel filter in the hose line to the solenoid valve. That helps keeping the gunk out of the valve. The manifold is not difficult to remove - you have to have 3/8" drive allen head socket and a set of extensions etc There is typically a good amount of junk on the inside of the manifold - it will not cause any "choking" though. The soot is from the EGR bypass valve and oil mist is coming from the valve cover vent that can get worse with engine wear. The black smoke has most likely other causes: one or more faulty injector nozzles. It can also be a stretched timing chain that causes the injection timing to be off. Then there is the ALDA controller right on top of the injection pump. People tend to mess with it not knowing what they are doing. There could be a ripped seal/ diaphragm in there. Do not make any adjustments without checking if the components are ok. This is best left to check by a great MB tech or other tech who has been doing this for a while. Then I hope you are not a new owner of a vehicle that the previous owner tried to roll coal with - that can really mess with the engine and put a good amount of extra soot into your oil but also back into the intake manifold. Hope this will help a little.
thx for your vids, i have a question about a 91 560sec when i first drive the car it wont shift to second until i hit 3500rpm and let off the gas, the warmer the trans gets the better it shifts, starts shifting smooooooth, any ideas thx again.
Is this symptom new or has the car always done this? If I am not totally mistaken, the later GenII KE Jetronic cars were programmed to idle higher and also rev higher before upshifting to let the engine warm up faster. If this phenomenon is new, then that is most likely due to debris stuck in the valve block. You can see if changing the ATF and filter will help any.
@@straybenzes thx for the info. I just bought the car a few months ago. So it was doing it when I bought it. But I did have a guy go thru the tranny like so said when the car gets warm it does shift normal. Thx again
The gas engines do not have the turbo boost limited which this solenoid regulates. However, the transmission does get its shift impulse through vacuum controlled pod at the driver side of the transmission. Mercedes Source sell an upgraded one that still may need a little tweaking. Also, there is a rubber cap supposed to be covering the pod. If that one is missing or has cracks it can cause rough shifting. Good luck sorting this out.
Dude I just bought the car this month, it’s not shifting right, I checked the transmission fluid it was low. Topped it off and it still did that, tomorrow I will try this and will see what happens
@@nasthedj3939 If the vac leaks have been addressed then check the tranny's vacuum modulator mounted on the driver's side of the tranny. It has a dial on top. This can be the issue. Unfortunately, it can also be due to debris in the modulator block deep within the tranny. There is a video about that on the channel.
Hello, should there be a constant 12v on the connector, on my 124 Coupe (m104.992 gearbox 722.5) there is no voltage in the connector, please explain to me what that part is for? There are two such same valves, one in front of the shock absorber cup and the other behind the master cylinder...Gearbox flare between 3 and 4 gear ( sometimes behaves normally, depends on how much I press the accelerator pedal), other speeds work very smoothly. Can it be because of those valves, and because of the voltage, or is it something else? Number of vacuum solenoid valves is 001 540 70 97. Sorry for my bad english.
Hi Milan. Your English is perfect. The OM603 with the oder 722.3 works very different than the updated and partially electronically controlled gas engine with the 722.5. Benz transmissions of that era are very reliable as long as they get maintained. Assuming the transmission has no oil leaks and has seen proper oil level and has not been abused it comes down to tracing any vacuum and electronic component issues first. If you have not changed the oil and filter yet I would drop the pan and see what you may find in the bottom. Look for small black flakes as those are a sign of the brake bands wearing. That by itself can cause slipping. This debris tends to also clog the valve and screen passageways inside the valve block. Good luck!
@@straybenzes Thanks a lot for the answer, I forgot to mention that the car is driven very little, the oil and filter have been changed, maybe you are right that something is clogged because the car is driven a little so it comes to slipping.I read somewhere that a faulty vacuum transmission modulator can be the cause of a slipping. I am interested in whether the connectors from vacuum solenoid valve should have a voltage of 12V, there is no voltage on my car?
@@straybenzes There is no voltage at standstill, when the engine is running there is also no voltage, I am a little confused, maybe the voltage comes only when the car is moving. I don't know exactly when it started, reading on the internet I discovered that the green vacuum hose coming out of the vacuum solenoid valve has something to do with the gearbox, so I thought the gearbox was slipping because of it, I accidentally took a voltmeter and measured...Sorry if I bother you with my stupid questions
@@milanobradovic7403 There is never a stupid question. That vacuum line is indeed the one that does determine when the tranny is supposed to shift. The line goes to the modulator valve. That valve sometimes causes rough shifting between gears, but usually does not cause a slip in 3rd or 4th. The solenoid valves typically prevent transmission overload and only cut the vacuum when that happens. So I am not surprised that you were not able to detect voltage there. Sounds like you do not regularly work on transmissions. I would contact a shop or person who does this for living and let them diagnose this issue for you. Most average shops will typically try selling you a rebuild or a used / new transmission. Good luck!
Can anyone help me to solve problem with mine gearbox? It's a 4-speed automatic in w140 s500. The problem is quite strange, because gearbox changes gears so smooth, without any problems, but it changing it too fast, when i'm starting to roll from second, gearbox changes to 3rd and 4th gear too early, on low speed, low rpm's, cruising about 25mph it shifts to 3rd and few mph higher it shifts to 4th. I need to kick it very deep to keep at lower gears. And even at full power it's going higher gears at 4.5- 5k rpm
Hmm. What model year is this? For a 1996 and younger one you can try resetting the adaptive transmission. Reset the transmission control module in any Mercedes from 1996 to 2016, 5 speed 722.6 and 7 speed 722.9 transmissions. Procedure: 1- turn key on 2 clicks. 2- press gas pedal down pass kick down switch and hold for 10 seconds. 3- turn key off. 4- release gas pedal. 5- wait 2 minutes with doing anything.
@@bossnox Before going into the complicated and expensive "fixes" let review what happened and when. When did this problem start? What is the fluid level in the tranny and what color is it? What is the mileage on the tranny?
The vacuum system is very similar also not identical. I would first start with checking the vacuum level in your system at idle. You should get at least 29"Hg vacuum. If you are in the low 20s then you have a leak and that is most likely your problem. Here is also an interesting thread about vacuum shift adjustments. forums.mercedesclub.org.uk/index.php?threads/hard-shift-transmission.127038/
@@straybenzes Oh, you brilliant SOB...your video have saved me some quid for certain mate as i've located a vacuum hose had separated from its receiving end and was resolved quite simply by joining the hose in its proper place. smooth shifting resolved in all of 15 seconds. THANK YOU SOO MUCH FOR SHARING YOUR KNOWLEDGE WITH THIS COMMUNITY!! ...
That depends on a lot of variables, but here are a few things that you can do before looking to rebuild the tranny. Drop the pan and see if you have any brake band flakes or other debris in there. Change oil and filter (do not forget to drain the torque converter). Check the vacuum on your vac system (0.5 Bar or 15"Hg minimum). If it still shifts rough it could also be the vacuum modulator on the tranny. It is the only device on the 722.3 tranny with a vacuum line. If it still shifts rough and you are brave you can drop the pan again and remove the intermediate plate and clean it and the small oil screens hidden there (@5.17min in this video: th-cam.com/video/pXYddrNBUbo/w-d-xo.html). If you find brake band flakes in the valve body and screens you may need a rebuild. As a last ditch effort you can try using Lucas oil and that usually helps - but you are just buying yourself a little time. Good luck.
Sorry for just answering now. If the engine has good power I would focus on checking on vacuum leaks. The little rubber cover on the tranny vac modulator is a frequent offender. Did you do a full fluid and filter replacement? Were there any foreign objects in the oil pan? If so, where there any black flakes in it?
This video saved me a lot of time and probably money trying to find the reason my car was slow and not boosting. I looked at the small black part of the hose and indeed it was split just before the fitting on the intake manifold. My metal fitting was also totally blocked and I used a tiny drill bit to completely clean it. Followed your procedure and now the car runs so much better. Transmission shifts are still not smooth but that problem is further down the vacuum system and I now think I know enough to try and fix it - THANK YOU!
Wow! Way to go. All the best to you.
This worked for the W123 and THANK YOU. Mine was disconnected, now it shifts SO SMOOTH!!
Thanks for letting me know. It also should have more power now.
Thank You so much for making this video! A tremendous help!
Nice, glad it helped.
Very useful and well explained.
Thanks!
Thanks! Helped me a lot!
Glad it did. All the best.
Thanks Ralph!
Glad you liked it.
Good info thanks !
:)
Thanks a lot!
Glad you are enjoying it.
1989 Mercedes’ 260 E rough transition shifting fix
First make sure that your engine vacuum is ok. Most of the time it is the vacuum activated transmission modulator. It is adjustable by removing the plastic cover and turning the adjustment counterclockwise to soften the shifts. The modulator is located in the driver side (left) of the transmission. There is a vacuum line leading to it. Make sure it is tight and not leaking.
Do not make big adjustments to your modulator. Do this in small increments. Most of the time, only a few degrees will be enough to change the shifting behavior.
Awesome! I bet mine is all gunked up.
Thanks!
:)
Hello Ralph I know I’m driving you crazy I have to ask you one last question I think that valve stays open in fact I know it stays open I did not put the lids on it but I had my son turn the switch back-and-forth no clicking that connects to my intake and the pump the transmission is not jerking only when the car is cold it gives you that little jerk head shift when it warms up smooth does that have anything to do with my turbo or overboost or under boost would it be better to stay closed or open I know I need a new one but if you can specifically tell me the most important thing that thing does I noticed another one next to the blue flying saucer and I don’t know what that one does and if it’s working Please let me know thank you Ralph thumbs up wish you were here in Michigan you’re a genius One more thing when the key is in the ignition does it always stay in the close Position when does that open when you give it gas or it stays closed thank you
The solenoid closes only when there is too much boost pressure. That is why it does not "click" when you turn the ignition on and it does not close even with the engine running at idle or normal load. This is the reason why you should check the condition occasionally to make sure that there is no oil and soot plugging it because that causes low power and rough shifting.
The blue "saucer" is the vacuum amplifier. They can go bad, but that would not be my first step in troubleshooting your cold rough shift issue. The 722.3 tranny does tend to have a one or more rough shifts that go away. Assuming you got all vacuum leaks addressed (and I can not overstate how important a good vacuum level is) I would focus your attention on the rubber mushroom cap of the vacuum modulator valve at the tranny. That cap dry rots and replacing it may already cure your issue. Also, under that cap is a dial that you can make an adjustment with by turning it a click to the left or right. That would not be my first thing to check. First thing would be checking tranny fluid level and condition. Change it including draining the torque converter as well as the oil filter and pan gasket. Good luck.
Hello Ralph love your videos keep them coming need to ask you a question about my actuator on my turbo I drove the car around let it heat up good and gave it some high Revolutions I did not see the actuator move at all could you please help thank you sir I think it is seized from all the stuff inside anyway to clean that without taking everything apart I’m just not good at that any suggestions please thank you
What do you call your turbo "actuator"?
I cannot move the Rod that connects to the waist gate I was thinking of spray intake cleaner I don’t know if it’s it’s all caked up or frozen but it is not moving at all to relieve the turbo From too much pressure I tried to move it but it’s just stuck
@@abrahamghannam2137 Well, if it is stuck it would most likely be in the "closed" position. With that being the case you would have plenty of boost and the overload protection relay valve should get a work out. Test the boost pressure with a 15psi pressure gauge in gear three at 4000rpm at the three different locations. You should have around 13 to 14.25psi there. If the overload valve is working, the white vacuum plastic hoses and connectors are ok, and the boost pressure control valve to compressor housing is ok then its time for a new to you turbo. That is about as far as I can help.
Hi, is it normal for w126- when I back up the sloped driveway and I let go of the accelerator my 560 sel will roll forward despite the fact that it is in R gear. Transmission changes gears flawlessly not grinding or anything but I find it weird that it rolls forward when in reverse- all by other (automatic tranny) cars would just stay in place. Btw- your videos did help me to worth things out thus I’m subscribing. Thanks
There is nothing to worry about here. This is completely different from car to car.
Hi, thanks for this! Any idea if it is the same on w124 250d 1989?I didn't find that valve in my engine compartment...Thanks
Hi Bobby. I believe you have the OM602 engine with either the 4G Tronic 4 speed or the 5 speed 722.5 transmission in your car. That is quite a different set up and there should not be a valve in the video on your car.
👍👍👍
Thanks!
I think my switch is bad on my 1987 SDL I noticed another one under the blue flying saucer or next to it the guy that I bought the car from had all the hoses rigged I tried to put everything back the right way I don’t know the exact routing of the vacuum tried looking online and can’t find anything right if that switch is bad what kind of damage would that do to the car or engine does that lower my boost I don’t feel any suction from neither if you can show me the vacuum routing hose to the engine or pictures I’ve been looking online can’t find anything I know you’re a boss at this I seen all your work you kick everybody’s ass please help thank you sir I’ll be waiting for your response
Hi there. That sounds like a mess. Make absolutely sure that you sniff out your vacuum leaks and that the hoses and vac pods are in the correct spot. Here is the 1987 vac diagram: www.benzworld.org/cdn-cgi/image/format=auto,onerror=redirect,width=1920,height=1920,fit=scale-down/i323.photobucket.com/albums/nn447/Jeremy5848/1987%20Mercedes%20300D/Vacuum603.jpg That should help sort out the vac line routing. Good luck.
Hi, its a very nice video! But i have a question for you, i've got my own '91 w124 230e Automatic and when i put the transmission gear from P to D it feels so rough and makes the car a little bit shaky and also makes the rpm drop to 600 rpm from 700/800. But in the other hand, the gear shifting is normal when the car is running from 2nd gear, to 3rd gear and so on. Thanks.
That is most likely the tranny's shift modulator. Located on the driver's side. It does have some adjustment on top, but most likely you are better off going with a new one. Good luck.
@@straybenzes thank you so much for the advice!
@@vin2386 You bet!
Somebody said I could take the actuator rod off put some PB blaster on there and try to free the actuator gate open but I have one of those bubbles like a catalytic converter that’s hiding everything and the screws are almost impossible to get to any suggestions getting plenty of boost in fact too much boost If I can free that Rod everything will be OK just getting to it
Well, that "bubble" is the so called trap oxidizer. There was a service campaign from Benz that had dealers replace this part with a straight piece of cast iron pipe. The trap oxidizer used to fail on people losing power to the point of turbo/ engine failure. I doubt you will be able to get that done for free +30 years later, but you can at least try getting rid of this thing as soon as possible. This very part may be the cause of your trouble. Here is a post (of many) concerning this part. mercedesforum.com/forum/diesel-discussions-33/trap-oxidizer-replacement-24842/
Hi Ralph I got one problem I don’t wanna bother you no more I need to ask you one last question the hard line coming from the fuel injection pump valve yes birding diesel fuel right from the top of where it sits inside The nozzle on the pump I can wiggle the hard line coming from the pump no matter how much I tighten it I had change the copper crush washers and the rubber O-rings was good till today I can move that hard line and I will be sporting diesel in the car is running I don’t know where to get the hardlinesAnd is it the hard line
I think you are talking about the hard plastic lines. ECS may be able to help you: www.ecstuning.com/b-genuine-mercedes-benz-parts/fuel-hose/6150700632/
Hello stray went to check the pressure switch pulled the rubber hose off the top of the manifold put a needle inside and pulled out a bunch of garbage sludge just on the tip of the needle I cannot imagine on the inside of the intake what it looks like blew through the pressure switch free did not check it with ignition I have to really push down on the gas pedal or should I say diesel on my STL before the turbo spool’s up and it’ll jump and go you will see a lot of smoke when I jump on it seems like it is choking if I drive like an old man car drives good but when I have to go I have to push the pedal all the way down to hit that passing Geer then the turbo kick in a lot of black smoke I think my intake is just plugged up with crap any suggestions they told me to take out the intake and clean it it looks like a huge job I hope it is not my turbo I can hear it’s cooling up nicely and then winding down there is a crack in a little flex pipe that’s on the manifold right next to My EGR they said I would have to disassemble everything to replace that little bracket which cost eight bucks please help thanks
There is a lot to answer to in here. First of all, yes it is that oil and soot mixture that can plug up the fitting, hose, and the solenoid valve. Give that a good cleaning. You may want to install a good size fuel filter in the hose line to the solenoid valve. That helps keeping the gunk out of the valve.
The manifold is not difficult to remove - you have to have 3/8" drive allen head socket and a set of extensions etc There is typically a good amount of junk on the inside of the manifold - it will not cause any "choking" though. The soot is from the EGR bypass valve and oil mist is coming from the valve cover vent that can get worse with engine wear.
The black smoke has most likely other causes: one or more faulty injector nozzles. It can also be a stretched timing chain that causes the injection timing to be off. Then there is the ALDA controller right on top of the injection pump. People tend to mess with it not knowing what they are doing. There could be a ripped seal/ diaphragm in there. Do not make any adjustments without checking if the components are ok. This is best left to check by a great MB tech or other tech who has been doing this for a while. Then I hope you are not a new owner of a vehicle that the previous owner tried to roll coal with - that can really mess with the engine and put a good amount of extra soot into your oil but also back into the intake manifold. Hope this will help a little.
Stray Benzes Thank you very much for replying you’re the only one that helps really helps me thank you Ralph😀
thx for your vids, i have a question about a 91 560sec when i first drive the car it wont shift to second until i hit 3500rpm and let off the gas, the warmer the trans gets the better it shifts, starts shifting smooooooth, any ideas thx again.
Is this symptom new or has the car always done this? If I am not totally mistaken, the later GenII KE Jetronic cars were programmed to idle higher and also rev higher before upshifting to let the engine warm up faster. If this phenomenon is new, then that is most likely due to debris stuck in the valve block. You can see if changing the ATF and filter will help any.
@@straybenzes thx for the info. I just bought the car a few months ago. So it was doing it when I bought it. But I did have a guy go thru the tranny like so said when the car gets warm it does shift normal. Thx again
@@chuckho8950 That makes sense. Thanks.
👍thank youuuuuu 👍🫡
Glad it helped.
I wish I cld message you I replaced the eha now I found a broken vacuum valve do you have a video working with that
Where does that broken valve sit and what does it look like?
Will that be the same for a 90 W126 420SEL?
The gas engines do not have the turbo boost limited which this solenoid regulates. However, the transmission does get its shift impulse through vacuum controlled pod at the driver side of the transmission. Mercedes Source sell an upgraded one that still may need a little tweaking. Also, there is a rubber cap supposed to be covering the pod. If that one is missing or has cracks it can cause rough shifting. Good luck sorting this out.
Dude I just bought the car this month, it’s not shifting right, I checked the transmission fluid it was low. Topped it off and it still did that, tomorrow I will try this and will see what happens
The best of luck to you!
Hey I changed all the vacuum hoses and that part works, and it’s still jurking bad, and what is that blue thing
@@nasthedj3939 If the vac leaks have been addressed then check the tranny's vacuum modulator mounted on the driver's side of the tranny. It has a dial on top. This can be the issue. Unfortunately, it can also be due to debris in the modulator block deep within the tranny. There is a video about that on the channel.
Hello, should there be a constant 12v on the connector, on my 124 Coupe (m104.992 gearbox 722.5) there is no voltage in the connector, please explain to me what that part is for? There are two such same valves, one in front of the shock absorber cup and the other behind the master cylinder...Gearbox flare between 3 and 4 gear ( sometimes behaves normally, depends on how much I press the accelerator pedal), other speeds work very smoothly. Can it be because of those valves, and because of the voltage, or is it something else? Number of vacuum solenoid valves is 001 540 70 97. Sorry for my bad english.
Hi Milan. Your English is perfect. The OM603 with the oder 722.3 works very different than the updated and partially electronically controlled gas engine with the 722.5. Benz transmissions of that era are very reliable as long as they get maintained. Assuming the transmission has no oil leaks and has seen proper oil level and has not been abused it comes down to tracing any vacuum and electronic component issues first. If you have not changed the oil and filter yet I would drop the pan and see what you may find in the bottom. Look for small black flakes as those are a sign of the brake bands wearing. That by itself can cause slipping. This debris tends to also clog the valve and screen passageways inside the valve block. Good luck!
@@straybenzes Thanks a lot for the answer, I forgot to mention that the car is driven very little, the oil and filter have been changed, maybe you are right that something is clogged because the car is driven a little so it comes to slipping.I read somewhere that a faulty vacuum transmission modulator can be the cause of a slipping. I am interested in whether the connectors from vacuum solenoid valve should have a voltage of 12V, there is no voltage on my car?
@@milanobradovic7403 At standstill there should not be voltage. These only get activated while driving. When did this trouble start?
@@straybenzes There is no voltage at standstill, when the engine is running there is also no voltage, I am a little confused, maybe the voltage comes only when the car is moving. I don't know exactly when it started, reading on the internet I discovered that the green vacuum hose coming out of the vacuum solenoid valve has something to do with the gearbox, so I thought the gearbox was slipping because of it, I accidentally took a voltmeter and measured...Sorry if I bother you with my stupid questions
@@milanobradovic7403 There is never a stupid question. That vacuum line is indeed the one that does determine when the tranny is supposed to shift. The line goes to the modulator valve. That valve sometimes causes rough shifting between gears, but usually does not cause a slip in 3rd or 4th. The solenoid valves typically prevent transmission overload and only cut the vacuum when that happens. So I am not surprised that you were not able to detect voltage there.
Sounds like you do not regularly work on transmissions. I would contact a shop or person who does this for living and let them diagnose this issue for you. Most average shops will typically try selling you a rebuild or a used / new transmission. Good luck!
Could that gunk in my intake cause all this?
Yes it can. The more blow by and the more your turbo leaks oil the more of that black stuff can go into the little valve.
Can anyone help me to solve problem with mine gearbox? It's a 4-speed automatic in w140 s500. The problem is quite strange, because gearbox changes gears so smooth, without any problems, but it changing it too fast, when i'm starting to roll from second, gearbox changes to 3rd and 4th gear too early, on low speed, low rpm's, cruising about 25mph it shifts to 3rd and few mph higher it shifts to 4th. I need to kick it very deep to keep at lower gears. And even at full power it's going higher gears at 4.5- 5k rpm
Hmm. What model year is this? For a 1996 and younger one you can try resetting the adaptive transmission. Reset the transmission control module in any Mercedes from 1996 to 2016, 5 speed 722.6 and 7 speed 722.9 transmissions.
Procedure:
1- turn key on 2 clicks.
2- press gas pedal down pass kick down switch and hold for 10 seconds.
3- turn key off.
4- release gas pedal.
5- wait 2 minutes with doing anything.
@@straybenzes it' a 1995 w140 s500, with 4spd tran.
@@bossnox Before going into the complicated and expensive "fixes" let review what happened and when. When did this problem start? What is the fluid level in the tranny and what color is it? What is the mileage on the tranny?
hmmm, is this configuration similar in '95 E300 deisel, by chance? experiencing similar hard shifts?
.
The vacuum system is very similar also not identical. I would first start with checking the vacuum level in your system at idle. You should get at least 29"Hg vacuum. If you are in the low 20s then you have a leak and that is most likely your problem.
Here is also an interesting thread about vacuum shift adjustments. forums.mercedesclub.org.uk/index.php?threads/hard-shift-transmission.127038/
@@straybenzes Oh, you brilliant SOB...your video have saved me some quid for certain mate as i've located a vacuum hose had separated from its receiving end and was resolved quite simply by joining the hose in its proper place.
smooth shifting resolved in all of 15 seconds.
THANK YOU SOO MUCH FOR SHARING YOUR KNOWLEDGE WITH THIS COMMUNITY!!
...
@@djrv3n423 Oh my! That is an epic response. Glad it all worked out. All the best!
@@straybenzes Can't thank you enough. I've subb'd for future videos to acquire more mercedes knowledge.
@@djrv3n423 Oh, thank you!
My 92 r129 shift kinda hard out of first gear
Yeah except that R129 have a different tranny and this video does not apply.
what if its just rough when shifting?
That depends on a lot of variables, but here are a few things that you can do before looking to rebuild the tranny. Drop the pan and see if you have any brake band flakes or other debris in there. Change oil and filter (do not forget to drain the torque converter). Check the vacuum on your vac system (0.5 Bar or 15"Hg minimum). If it still shifts rough it could also be the vacuum modulator on the tranny. It is the only device on the 722.3 tranny with a vacuum line. If it still shifts rough and you are brave you can drop the pan again and remove the intermediate plate and clean it and the small oil screens hidden there (@5.17min in this video: th-cam.com/video/pXYddrNBUbo/w-d-xo.html). If you find brake band flakes in the valve body and screens you may need a rebuild. As a last ditch effort you can try using Lucas oil and that usually helps - but you are just buying yourself a little time. Good luck.
Sorry for just answering now. If the engine has good power I would focus on checking on vacuum leaks. The little rubber cover on the tranny vac modulator is a frequent offender. Did you do a full fluid and filter replacement? Were there any foreign objects in the oil pan? If so, where there any black flakes in it?
Why is he checking the overboost solenoid for a transmission shifting problem? That is not even vacuum…. Its boost 😀
For the grins of it go ahead and plug the line after that solenoid.
420 sel vacuum check value
The SDL is different from the gas engine model vacuum system.
Hello.
Mine is not shifting smoothly. I will try it. Thanks
The best of luck to you!
Scotch Locks smh
^\o/^