Have a Car Question? Ask a Mechanic Online.
Hello I may beable to point you in the right direction.
That would be great
Typically a high idle indicates a vaccuum leak, it seems like in your circumstance it may be sporratic.
its been consistent lately, high every morning until i reset it with the battery trick
You can open the hood and just looks around for any cracked vacuum hoses If you have the opportunity have a vacuum test done on the vehicle. When you disconnect the battery the car goes into "Safe Mode", and operates on a set list of conditions.
This is most likely why a vacuum leak would not effect the performance once reset,, A vacuum leak will allow a pressure differntial allowing the vehicle it run higher ( the absence of vacuum indicates open throttle to the computer).
I would suggest have a vacuum test done and the MAP or MAF sensor checked, that seems tobe the cause of your worries.
MAF ( Mass Air Flow )
MAP ( Manifold Absolute Pressure )
ok, i have checked the hoses and nothing is real obvious. I have read it may be intake gaskets but really thought i would or might see coolant if that was the case. i will also have those checked, by the way, it runs great otherwise, no codes present either. does that mean anythng?
can i test for vac leaks at home easily or?
Your right it can be the intake manifold but doesnt necessarily mean you would see coolant. If the intake gasket is bad, it would cause a vacuum leak, this would also be a cause of the problem. Any vacuum leak, malfunction MAF sensor or possibly the IACV ( idle air control valve).
There is a trick,, I will be honest its not very safe, but it is a trick many tech's use. Spraying something flammable ( Brake Cleen) over the vacuum lines and manifold. If there is a leak than the flammable liquid is pulled in from the leak point and you will hear a change in the tone of the engine. That is where you leak would be coming from. Again I wouldn't recommend you doing this, have a certified tech look at it.
The good news, its most likely not a serious problem, hopefully it is a small crack on the bottomside of a vacuum line, which is very common.
Ok. Thanks a bunch. also whats the chances of it being a swich on the pwer steering pump causing the idle to increase? Just one of the things I read. Again thank you.
I meant to say "intake manifold gasket" earlier. My mistake
That is a possibility, I have yet to see that on a vehicle but it is possible and I can explain why. When you turn the steering wheel a drain is put on the engine due to the hydraulics needed to power the rack and pinon. The sensor will tell the computer that "hey the car is running at idle ( say in a parking lot turning the wheel) and there is not enough power to sustain the RPM's without stalling" So the sensor indicates that the idle needs to be raised to compensate for the strain on the engine, by raising the idle.. So yes that is possible.
one more thing. any ideas about the loud suction from the intake box? The throttle blade is always in the right place it seems, its loud! Then it goes away too.
This also is probably die to the "safe mode", I would need to actually see the car.
Thanks for dumbing it down for me, I will try those suggestions and see what happens.
No problem, please accept and leave some feedback. Feel free to contact me anytime, I have worked on all makes and models. Have a great day!