Extreme vibration at idle along with a slight oscillation and a subtle lack of power at high rpm is a good indication of a burned valve. The unburned fuel from lack of compression could also contribute to the P0172 code. In your case it may just be the tiniest fleck the cooked and shipped off. I would suggest doing a compression or a power balance test to isolate the cylinder which is having issues and go from there. Should be able to see the exhaust valves somewhat with a borescope through the spark plug hole.
Thanks so much for the reply! I hadn’t considered anything like a burned valve. At this point it runs well enough so I’m just kind of going with the flow. Could use O2 sensors and I’m thinking about maybe doing a new ETM in hopes that it will improve idle. Thanks again!
Thanks for watching! I am pretty certain that is is the Electronic Throttle Module which is a common point of failure on these cars. This is still the original unit (they were replaced under a recall but the window for that has passed). There is a company called XemodeX which sells remanufactured ETM units. They run about $700 I think. It probably is easy to swap but I am just a little afraid of messing it up I guess! Also the price. The car runs well enough but the throttle response just isn’t what it should be. I probably will end up replacing it in time.
Thanks for watching. Yeah actually a few months after this video Volvo did replace the top motor mount but sadly that did not seem to help. As I learn more about these cars I’m down to thinking that the oxygen sensors probably are original and need changing, which I’m hoping helps. I am worried though that it’s misfiring due to oil in the spark plug wells (verified when changing plugs) caused by the dreaded PCV system building up too much pressure.
if you did a cat back NON volvo brand this will happen as the tubes are not heavy duty and you will get the vibration …. my non volvo cat back had the same issue on my 98 s70....also check the top engine mount may be torn and getting a vibe as mine was a poly one that I didn't like as the dash would shake like the shifter in the video does....
Thanks much. Yeah the exhaust was not of the best quality, which a shop told me a while back. A hard (and expensive) lesson learned. Will look at engine mounts also. Take care!
Hi- Sadly I haven’t! But I believe I have it narrowed down to the ETM (throttle) which is a notorious point of failure on these vehicles - and/or tired oxygen sensors. At this point it is a matter of $$$. I would like to do the work myself but I lack the time and the workspace. I also am reluctant to go to a shop because of the cost. I have spent way too much on this car haha. But it runs ok and gets me around. At some point I will probably just end up bringing it somewhere. Stay tuned and take care!
@@jimmccarron Hello my friend, my son has a 1997 2.5 auto which had a similar problem. We spent £££ in the auto shop but eventually an independent Volvo mechanic fixed it for us by replacing the plug leads, distributor cap and rotor arm. Runs great now, perfect at tick over. Have you considered this? Good luck.
@@v4nno Hi, thanks for writing. I replaced plugs and ignition coils shortly after getting the car to no avail. Maybe a wiring problem. I may take it to a shop and see what they can find.
@@jimmccarron I've been having a litteny of problems with my 2000 Volvo V70. Really bad idle. I've replaced the MAF, O2 sensor, rebuilt throttle body (that cost $$$), and now I'm doing the plugs and coils after finding them to all be in bad condition. Gonna try the MAP sensor next if that doesnt fix it. I'm also checking all the ground points in the engine bay for corrosion. I've only had the car 3 weeks and all this started happening 1 week in. Pretty frustrating.
Extreme vibration at idle along with a slight oscillation and a subtle lack of power at high rpm is a good indication of a burned valve. The unburned fuel from lack of compression could also contribute to the P0172 code. In your case it may just be the tiniest fleck the cooked and shipped off. I would suggest doing a compression or a power balance test to isolate the cylinder which is having issues and go from there. Should be able to see the exhaust valves somewhat with a borescope through the spark plug hole.
Thanks so much for the reply! I hadn’t considered anything like a burned valve. At this point it runs well enough so I’m just kind of going with the flow. Could use O2 sensors and I’m thinking about maybe doing a new ETM in hopes that it will improve idle. Thanks again!
Vacuum hoses and boost pressure hoses are a common issue as well. It will cause the car to cut out under load or idle.
Thanks! Yeah I do hear any vacuum leaks but will check.
Love the exhaust in this these S70’s. Did you figure, what the problem with idle was ?😊
Thanks for watching! I am pretty certain that is is the Electronic Throttle Module which is a common point of failure on these cars. This is still the original unit (they were replaced under a recall but the window for that has passed). There is a company called XemodeX which sells remanufactured ETM units. They run about $700 I think. It probably is easy to swap but I am just a little afraid of messing it up I guess! Also the price. The car runs well enough but the throttle response just isn’t what it should be. I probably will end up replacing it in time.
Maybe motor mounts as far as the vibration, apparently the one mount on the top is famous for needing to be replaced.
Thanks for watching. Yeah actually a few months after this video Volvo did replace the top motor mount but sadly that did not seem to help. As I learn more about these cars I’m down to thinking that the oxygen sensors probably are original and need changing, which I’m hoping helps. I am worried though that it’s misfiring due to oil in the spark plug wells (verified when changing plugs) caused by the dreaded PCV system building up too much pressure.
if you did a cat back NON volvo brand this will happen as the tubes are not heavy duty and you will get the vibration …. my non volvo cat back had the same issue on my 98 s70....also check the top engine mount may be torn and getting a vibe as mine was a poly one that I didn't like as the dash would shake like the shifter in the video does....
Thanks much. Yeah the exhaust was not of the best quality, which a shop told me a while back. A hard (and expensive) lesson learned. Will look at engine mounts also. Take care!
Wish my 98 S70 Volvo idled that low. My idles at 2
Wow yeah that’s up there. Order thought would be throttle position sensor but could be mass airflow sensor or IAC.
@@jimmccarron Its throwing both codes but just blew camshaft sensor too
@@aprilzerkle3473 did you figure it out ?
Did you fix this problem?
Hi- Sadly I haven’t! But I believe I have it narrowed down to the ETM (throttle) which is a notorious point of failure on these vehicles - and/or tired oxygen sensors. At this point it is a matter of $$$. I would like to do the work myself but I lack the time and the workspace. I also am reluctant to go to a shop because of the cost. I have spent way too much on this car haha. But it runs ok and gets me around. At some point I will probably just end up bringing it somewhere. Stay tuned and take care!
@@jimmccarron Hello my friend, my son has a 1997 2.5 auto which had a similar problem. We spent £££ in the auto shop but eventually an independent Volvo mechanic fixed it for us by replacing the plug leads, distributor cap and rotor arm. Runs great now, perfect at tick over. Have you considered this? Good luck.
@@v4nno Hi, thanks for writing. I replaced plugs and ignition coils shortly after getting the car to no avail. Maybe a wiring problem. I may take it to a shop and see what they can find.
@@jimmccarron I've been having a litteny of problems with my 2000 Volvo V70. Really bad idle. I've replaced the MAF, O2 sensor, rebuilt throttle body (that cost $$$), and now I'm doing the plugs and coils after finding them to all be in bad condition. Gonna try the MAP sensor next if that doesnt fix it. I'm also checking all the ground points in the engine bay for corrosion. I've only had the car 3 weeks and all this started happening 1 week in. Pretty frustrating.
Yeah that must be frustrating. But good on ya for putting in all that work. Best of luck!
Clean the throttle, its probably got a buildup
Thanks! I’ve learned some about the Electronic Throttles on these cars and how they are known to be problematic. Going to try to clean it.