If I remember correctly Paul, that thing you're unsure of is part of the automatic choke. As heat expands, it acts as s sort of thermostat that then works in conjunction with the idle system
Also with the tb seals, you can use a blind hole bearing removal tool, or bang them out from opposite ends. I just used a socket to persuade the new ones back in.
Great vid and yes that unknown piece I'm almost certain is a thermostatic style mixing valve. It coils and u coils based off coolant temp to let more /less coolant bypass through the tbody. A total waste especially since most of us just bypass the tbody coolant anyway
Good info from this video! At 1:38, the diagram shows Molybdenum Disulfide being used to seal off the gap of throttle plate. I think later evo TB’s doesn’t have the access port for that other component you took out near the coolant passage. I like this whole evo archeology stuff!
Whats odd to me is i never saw that "Molybdenum Disulfide" in the location shown on the front of throttle plate. Or is it not suppose to be "visible"? Perhaps the previous owner cleaned off the front of the throttle plate once in the past? If i'm not mistaken, it was the backside of my throttle body plate that people think was entirely coated.
@@BoostedFilms I didn’t see it either on my evo and also on my spare TB. I think it gets cleaned off easily. It’s not really “needed”, the biss screw adjustment will compensate for the the passage of air through the plate
Do I have to have the 'wax pellet' or can I just cap off the hole? When I plug it with my finger, it idols perfectly. Mine was missing when the car was given to me...
My Evo 8 MR has idle issue after warm up it goes super lean AF almost dies and then idle goes back up and repeats the process. Curious if you had a similar issue relating to that small part? Also does the Evo 9 throttle body eliminate that part altogether?
@@DJ_Driven that was the exact problem I had, I tried new FPR, MAP sensors,IAT, and BISS screw. Non of these fixed the problem. The evo 9 tb eliminated that part and that finally solved it.
@@FranchisePhoto This idle issue has been a major struggle. If I obtain a brand new OEM Evo 9 TB from Mitsubishi should come complete where I can just swap out and I'm good to go?
So having removed the biss screw myself, it throws off idle by a lot. It’s usually recommended not to touch it, but easy enough to recalibrate idle with the ecu flash, there’s a guide on the forums I believe.
EXTENDED THOUGHTS ON MYSTERY PART I have a Mitsubishi 6G74 engine. I've had trouble with high idle after cleaning the throttle body. That unknown part at 4:20 is something that I don't quite understand either but I'm hoping that it is the source of my high idling! In the aftermarket manual I have on my vehicle (Mitsubishi Magna) it lists a device as a wax pellet thermo valve. However, I don't believe that it is actually a wax pellet valve. A wax pellet valve is, according to TH-cam videos, a sealed device that is surrounded by engine coolant. When the coolant heats up and melts the wax within the module, the wax expands and pushes out a pintle which normally shuts of a small passageway for air to sneak around from one side of the throttle body into the air intake plenum/chamber. This mystery device, however, is not surrounded by engine coolant. It in fact, at least in my throttle body, lives just a bit off to the side but in the same space as the Idle Air Control chamber! The base holds a coiled spring-like metallic strip and at the end a black plastic "flap" clips in to a small plastic seat that sits in the end of the coil/spring. That flap is actually cream coloured once you clean the carbon off of it! Now when assembled that flap actually faces the pintle of the IAC module. When the pintle is fully extended, it moves quite close to that flap. What does this mean? I don't know. You would think that the mystery module heats up as the coolant that runs beneath the throttle body heats up. When it heats up along with the rest of the throttle body, the coil turns (like a bimetallic strip, perhaps?) and the coil turns that flap so that it slows down the rate at which air flows through that butterfly bypass passage. What I don't understand at present, though, is that when you first assemble the mystery device it appears to be in the position that most restricts the airflow through the IAC airflow chamber! I.e., it is already in the "talk to the hand" position whereas you'd think it would start in the paper (from rock, paper, scissors) position which would let the air glide over and under the plastic flap. I'm still working on my throttle body so will look at that component again very soon. Yes, it's a long comment but I'm sure only those truly interested will have read this far.
Finally. I had a look at my own bimetallic flap thingi today. In the chamber that houses the coil and the seat/base of the flap, there is an extra semi-circular recess. Now the seat/base of the flap has the third-circular protrusion that loosely fits into this semi-circular recess. What this means, I think, is that the flap doesn't actually turn that far. I think it starts by facing the end of the Idle Air Control (IAC) pintle. I suspect that when the coil heats up it turns the flap backwards by about 35 degrees, give or take. Can I say this? The IAC pintle is pretty obvious in what it does, i.e., the further out it protrudes, the more it blocks the flow of air in the "butterfly valve air bypass channel". Now, what the heck that flap does when it turns backwards a little bit after heating up, it's just not that obvious! I wish it was.
You are not supposed to remove all the black coating on the butterfly plate and inside wall of throttle body. Your idle will now be high because air now leaks through the plate. You need to buy a spray to reseal it again. I need to find my spray to find the name.
@@BoostedFilms I think it is called Dry Moly Lube spray I used to put back the coating. I sprayed the sides of where the flapper opens away and backwards (back side of top half and front side of bottom half). Also, notice that the black coating was on the back side of the throttle body (so it was intentionally sprayed there and not dirt from driving).
Also, once you are putting the plate back the final time, you may want to add a bit of blue loctite to the 2 screws so they can't come loose and fall off (and get sucked into engine).
![เปิดใจ "อาจารย์เบียร์ คนตื่นธรรม" อดีตเคยสุดทุกทาง ถ้าใช้หนี้หมดไปบวชแน่ l [Nickynachat]](http://i.ytimg.com/vi/IxeE0xVhy08/mqdefault.jpg)
You’ve helped me with my build more than you know lol. Just by documenting this all.
Happy to hear! Appreciate the comment.
If I remember correctly Paul, that thing you're unsure of is part of the automatic choke. As heat expands, it acts as s sort of thermostat that then works in conjunction with the idle system
Could you do a follow up video on how to properly adjust the TPS and also apply that coating recommended in the comments?
You the man! I ordered two new throttle body seals and this video helped.
Happy to help!
Also with the tb seals, you can use a blind hole bearing removal tool, or bang them out from opposite ends. I just used a socket to persuade the new ones back in.
Great vid and yes that unknown piece I'm almost certain is a thermostatic style mixing valve. It coils and u coils based off coolant temp to let more /less coolant bypass through the tbody. A total waste especially since most of us just bypass the tbody coolant anyway
Thanks for the info
Great video, good information on the throttle body components. Thanks Paul.
Thanks. I’m certainly not a expert here. Check the comments for updates and info from the evo community
Good info from this video! At 1:38, the diagram shows Molybdenum Disulfide being used to seal off the gap of throttle plate. I think later evo TB’s doesn’t have the access port for that other component you took out near the coolant passage. I like this whole evo archeology stuff!
Whats odd to me is i never saw that "Molybdenum Disulfide" in the location shown on the front of throttle plate. Or is it not suppose to be "visible"? Perhaps the previous owner cleaned off the front of the throttle plate once in the past?
If i'm not mistaken, it was the backside of my throttle body plate that people think was entirely coated.
@@BoostedFilms I didn’t see it either on my evo and also on my spare TB. I think it gets cleaned off easily. It’s not really “needed”, the biss screw adjustment will compensate for the the passage of air through the plate
I believe that unknown piece is a 'wax pellet' as others have mentioned, it shrinks/expands with the temperature helping regulate air flow/idle.
Do I have to have the 'wax pellet' or can I just cap off the hole? When I plug it with my finger, it idols perfectly.
Mine was missing when the car was given to me...
that mystery piece is what messed up my idle completely, I ended up switching to an evo 9 TB which eliminated that part and got the car back to normal
My Evo 8 MR has idle issue after warm up it goes super lean AF almost dies and then idle goes back up and repeats the process. Curious if you had a similar issue relating to that small part? Also does the Evo 9 throttle body eliminate that part altogether?
@@DJ_Driven that was the exact problem I had, I tried new FPR, MAP sensors,IAT, and BISS screw. Non of these fixed the problem. The evo 9 tb eliminated that part and that finally solved it.
@@FranchisePhoto This idle issue has been a major struggle. If I obtain a brand new OEM Evo 9 TB from Mitsubishi should come complete where I can just swap out and I'm good to go?
@@DJ_Driven I got mine used off eBay or somewhere, I only changed out the shaft seals to be safe. A used one should be fine
So having removed the biss screw myself, it throws off idle by a lot. It’s usually recommended not to touch it, but easy enough to recalibrate idle with the ecu flash, there’s a guide on the forums I believe.
Agreed. Hopefully most people watching understand i just wanted to take it all apart to view and show everything.
Hi,
Will u Plz tell me the part code for this IACV..?
I need it for mu Lancer 4g15 engine. It's having fluctuations in rpm.
Anyone know where someone can get a replacement screw for the "mystery component"?
EXTENDED THOUGHTS ON MYSTERY PART
I have a Mitsubishi 6G74 engine. I've had trouble with high idle after cleaning the throttle body. That unknown part at 4:20 is something that I don't quite understand either but I'm hoping that it is the source of my high idling!
In the aftermarket manual I have on my vehicle (Mitsubishi Magna) it lists a device as a wax pellet thermo valve. However, I don't believe that it is actually a wax pellet valve. A wax pellet valve is, according to TH-cam videos, a sealed device that is surrounded by engine coolant. When the coolant heats up and melts the wax within the module, the wax expands and pushes out a pintle which normally shuts of a small passageway for air to sneak around from one side of the throttle body into the air intake plenum/chamber.
This mystery device, however, is not surrounded by engine coolant. It in fact, at least in my throttle body, lives just a bit off to the side but in the same space as the Idle Air Control chamber!
The base holds a coiled spring-like metallic strip and at the end a black plastic "flap" clips in to a small plastic seat that sits in the end of the coil/spring. That flap is actually cream coloured once you clean the carbon off of it!
Now when assembled that flap actually faces the pintle of the IAC module. When the pintle is fully extended, it moves quite close to that flap. What does this mean? I don't know.
You would think that the mystery module heats up as the coolant that runs beneath the throttle body heats up. When it heats up along with the rest of the throttle body, the coil turns (like a bimetallic strip, perhaps?) and the coil turns that flap so that it slows down the rate at which air flows through that butterfly bypass passage.
What I don't understand at present, though, is that when you first assemble the mystery device it appears to be in the position that most restricts the airflow through the IAC airflow chamber! I.e., it is already in the "talk to the hand" position whereas you'd think it would start in the paper (from rock, paper, scissors) position which would let the air glide over and under the plastic flap.
I'm still working on my throttle body so will look at that component again very soon.
Yes, it's a long comment but I'm sure only those truly interested will have read this far.
OK. Did some Youtubing and found this at the 7 minute mark th-cam.com/video/yOVrMTB-MTI/w-d-xo.html
Finally. I had a look at my own bimetallic flap thingi today. In the chamber that houses the coil and the seat/base of the flap, there is an extra semi-circular recess. Now the seat/base of the flap has the third-circular protrusion that loosely fits into this semi-circular recess. What this means, I think, is that the flap doesn't actually turn that far. I think it starts by facing the end of the Idle Air Control (IAC) pintle. I suspect that when the coil heats up it turns the flap backwards by about 35 degrees, give or take.
Can I say this? The IAC pintle is pretty obvious in what it does, i.e., the further out it protrudes, the more it blocks the flow of air in the "butterfly valve air bypass channel".
Now, what the heck that flap does when it turns backwards a little bit after heating up, it's just not that obvious! I wish it was.
You are not supposed to remove all the black coating on the butterfly plate and inside wall of throttle body. Your idle will now be high because air now leaks through the plate. You need to buy a spray to reseal it again. I need to find my spray to find the name.
Interesting. Thanks. Yes please provide the name of the coating if you can.
@@BoostedFilms I think it is called Dry Moly Lube spray I used to put back the coating. I sprayed the sides of where the flapper opens away and backwards (back side of top half and front side of bottom half).
Also, notice that the black coating was on the back side of the throttle body (so it was intentionally sprayed there and not dirt from driving).
The throttle body seals are a pain to put back straight. Find a way to tap or push it in without destroying it by going in at an angle.
Also, once you are putting the plate back the final time, you may want to add a bit of blue loctite to the 2 screws so they can't come loose and fall off (and get sucked into engine).
@@donsevo89research74 thanks for the info. Very much appreciated
This is a waste of time , mines had a leak from the shaft seals , I replaced it an I felt no difference