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Discussion Starter · #1 ·
When I am in gear and release the gas pedal to press the clutch, the revs drop down abruptly creating a bucking, the severity lessens as I shift up the gears, gets barely noticeable 4->5. I can press the clutch in just before I fully release the gas to drive it manageably.

When I turn the car off then on again, it sometimes fixes the problem and the throttle application and release are normal (feels like butter compared to when its bucking). This problem is intermittent; it occurred maybe a month ago once, and has not happened again until today multiple times.

I also noticed that the problem coincides with my Cruise Control not working (the message "Cruise" on the dash does not come up when the problem is present), so this leads me to think it is more of an electrical issue than a pure mechanical, since it can be alleviated with a 'reboot' (?) ETM, TPS, ETC? I have 1 code for evap leak, p0442, but I had that before with no bucking issues, I suspect it is the J hose which I need to get underneath and check on.

Any help is appreciated, I hope to fix this myself as I am predicting it will be costly. Also I tried searching but my lack of terminology did not yield direct results to my issue.

Thank you.
 

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If not throttle body issues, clutch position switch issues. That or brake position switch issues, those are the two most common reasons for cruise not working. The clutch switch would also not let the engine management know you're pushing it so it might act goofy.

Hook up VIDA, there will be a code if either switch is bad or going bad.
 

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Discussion Starter · #4 · (Edited)
sounds like throttle body issues.

http://www.matthewsvolvosite.com/volvos-electronic-throttle-module-fiasco

has yours ever been replaced?
what happens is the pots in the ETm get dirty, so the computer loses it's reference for where the throttle blade is at.
I believe it has been replaced, I recall seeing some sort of sticker/marking on the module before indicating it was a replacement part of some degree. I will attempt to clean out the throttle body as my first step, I can imagine decent build up. Thanks.


If not throttle body issues, clutch position switch issues. That or brake position switch issues, those are the two most common reasons for cruise not working. The clutch switch would also not let the engine management know you're pushing it so it might act goofy.

Hook up VIDA, there will be a code if either switch is bad or going bad.

Thanks for the info, I will try to get someone to scan it for me as soon as possible.
 

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I believe it has been replaced, I recall seeing some sort of sticker/marking on the module before indicating it was a replacement part of some degree. I will attempt to clean out the throttle body as my first step, I can imagine decent build up. Thanks.
probably not going to do you any good. The pots are inside the unit.
take a look at the etm troubleshooting stuff at the mvs link. it's pretty comprehensive.
 

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I second Lloyds opinion. A dirty clutch position sensor really wrecked havoc on my s70 that a restart would fix


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I am facing quite similar issues with my 2001 V70 T5M. My cruise control has not worked whatsoever since I've bought the car, I have the P0442 evap code, and also an "Engine System Service Required" DIR message.

In addition to this, I have manifold pressure fluctuations at highway cruising speeds. Drops can be anywhere from 5-15 in. Hg. It seems strikingly similar to the discussion of symptoms of ETM failure found on MVS (symptom number 3, more specifically), which states,

Eventually, you’ll feel momentary hesitation when driving at highway speeds, almost as if there’s a gust of wind pushing the car back. When this happens, I look at shrubbery to see whether there is a significant wind – and, if there isn’t, then it’s likely to be the throttle, especially if it has lots of miles on it. At this stage, the car is in no danger of stalling, but it’s one of the last signs that you’re getting close to a true failure – figure 5 to 10 thousand miles remaining on the throttle.
I am wondering if it is the impending doom of ETM failure. In this case, would the ETM still be covered under warranty since I've read Volvo extended the warranty of the part to 200K miles or 10 years, and my V70 is at 136K miles and it's only been 7 years since the Marelli replacement.
 

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Discussion Starter · #9 ·
I am facing quite similar issues with my 2001 V70 T5M. My cruise control has not worked whatsoever since I've bought the car, I have the P0442 evap code
Have you addressed the evap code yet or the whole cruise control issue? I have not gotten around to fixing the code yet.
 

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May I join this thread?
Would you expand on the "restart" you mentioned? I've had some clutch position sensor issues and if you can enlighten me i would appreciate it.
 
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