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Discussion Starter · #1 ·
I've been having a problem lately when accelerating at an onramp.

I press down the pedal and I get no response unless i straighten out the wheel.

I did change the front right tire with a used one of the same size, and it's inflated to 38 PSI, same as the others.

I get the wheel slip symbol sometimes, and the car will only take off when I fully straighten the wheel. I can have the pedal down on the floor and still have no power.

Any ideas?

2007 v7 AWD 152,000km/94,500 miles
 

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get codes read. Your ECM is probably receiving bad feedback from one or more sensors and thinks it is impossible (or unsafe since it is a volvo) to accelerate.

should be something easy. do you have 4C?
 

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If the DSTC indicator light is flashing it means the system is working to prevent wheelspin or skidding.

Just for diagnostic purposes, try disabling DSTC and see if it makes any difference for acceleration.
 

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My wife's car (Jetta) had a similar condition and it turned out to be that one of the wheel speed sensor harness clips had broken and allowed the inside of the wheel to rub a hole in the protective cover of the harness. When she turned, the wheel would contact the exposed wires shorting them out causing the traction control the think the wheel was slipping. Just a thought.
 

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Discussion Starter · #5 ·
I have 4C. No codes from my Dice scan. DSCT off definitely makes a difference in acceleration. I'm fairly certain the sensors are the same that the ABS system uses. I'll have a look at the connections and make sure there aren't any contact issues.
 

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I had the same thing in mind as Jetmech. And yes, ieatglue. I believe the car pulls individual wheel speed signals from the ABS sensors and uses deviating speeds (calculated using the vehicles speed, I'm guessing from the TCM, compared to what each wheels' speed should be based on how much the steering wheel is turnt) to decide whether to engage traction control or anti-skid etc.

Since disabling DSTC helps it sounds very plausible the issue is a bad sensor. I haven't done this myself but I've read about others having this issue and I believe it's possible to measure their resistance. Not sure what value they should have but if you measure all four and one deviates then I'd guess that's your culprit.
 

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Discussion Starter · #7 ·
I'll hook up my Dice unit and see if I can do a diagnostics test or something. I'll try that tonight and report back!
 
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