I have a black, 1996 Volvo V90 that in the past month has begun acting up in an unsettling way.
My car has begun to do this weird lurching thing when I have my foot on the brake. It sounds as if I am revving the engine, or as if the engine is trying to turn over. It is nearly always when my foot is on the brake pad, and the car will make the revving sound and try to lurch forwards- as if my foot was not firmly on the brake. When it first happened I even looked at my foot placement on the brake pad to make sure I wasn’t accidentally pressing the gas with my shoe.
It usually happens after it has been sitting in the unshaded parking lot at my summer internship, within the first 20 minutes of starting the car, and usually when my foot is on the brake (because I am slowing or stopped at a light) but it has happened a few times when I have begun to accelerate from a slow speed or stop as well.
Recently, it did this while I was at a stoplight and it completely shut the engine off. It did this twice in that same drive home, but has not done it again in the past week (while it has kept doing the lurching thing and with much more frequency).
I have explained my problem to several people and two of them mentioned that it could be the idler, I will not be able to take it into a mechanic until a week from today as I am out of state and cannot find a good Volvo mechanic in my area.
In the meantime, is there any information you can give me as to what is causing this? Or any possible preventative measures I can take until next week when I take it in? This problem is stressing me out every time I get into my car and any advice is greatly appreciated.
First of all you do not need a Volvo mechanic for a 1996, it is a vehicle that just needs a good mechanic. Second don’t ruin your internship because you can’t spell brake.
Thank you Volvo V70 for your input. However I still feel more comfortable taking my car to it’s usual mechanic.
P.S.
Thank you ever so much for correcting my spelling. I am usually capable of spelling brake, but my fingers get away from me while I am quickly typing.
The IAC valve controls the engine idle speed whenever the accelerator is released and/or when the brake pedal is applied.
These IAC valves can be effected by heat where the valve will hunt for the proper idle speed which can cause the idle speed to increase/surge, or the IAC valve will prevent air from entering the engine causing the engine to stall.
Until you can get the vehicle to your regular mechanic, shift the vehicle into neutral when stopping. This may stop the IAC valve from hunting and may also prevent the engine from stalling.
Good idea by @Tester on the IAC, that’d be my first guess. An air leak which allows unmetered air into the engine can cause this too. Check any rubber boot-like gadgets that direct air from the air filter area to the engine intake, or in that pathway, for cracks or leaks. A full vacuum system check is a good idea for this symptom too.