Skip the auto shop - Our mechanics make house calls

Q: the car revs high and at stop signs while slowing down then idles down suddenly and sometimes stalls, whats the cause?

asked by on

ive replaced idle control valve, egr solenoid, and cam sensor, replaced with used parts, map sensor maf, sensor, throttle position switch, egr valve proved to be good, found no vacuum leaks in hoses, pcv and hose was good? im running out of ideas? questioning cam senso,r,cat converter, possible evac problem? kinda grasping at straws now

My car has 122000 miles.
My car has an automatic transmission.

A: The engine intake manifold seals or the int...

The engine intake manifold seals or the intake tubes between the mass air flow sensor and the throttle body may have a leak that you cannot hear, but could be found using a smoke machine designed to find the leaks. However, first, I would recommend having the engine’s computer scanned for any codes before checking for vacuum leaks. This can be done by you or by a mechanic.

A certified technician, such as one from YourMechanic, will have a smoke machine or some other type of vacuum leak detector to diagnose your revving and idling issue. There are some electronic detectors that may work as good as the smoke machine that may help in this case. After diagnosis, they can recommend a repair to have this issue resolved.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Engine makes metal-to-metal noise on a 2012 Ford Taurus SEL 3.5

If you are talking about engine noise, that means that the engine is on its way out. That generally means that the bearings on the crank are worn and that the pistons are making the clunking around. Because, instead of...

Q: Rough idling, hard shifting and shuddering at the highway

Thanks for writing in about your 2002 Isuzu Trooper. The rough idle may be due to the fuel injection system being dirty or having an engine vacuum leak causing a lean condition. The hard shifting and shuttering with the chirping...

Q: coolant coming out of radiator cap.

Hello. If the engine is overheating then there can be a number of things going on. I usually test the radiator cap, the thermostat, and the cooling fans. Any of these can fail and cause this. If these have been...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...