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.

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?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. the car revs high and at stop signs while slowing down then idles down suddenly and sometimes stalls, whats the cause?

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: Can you change the defected water pump without changing its defected belt (which is the drive belt and only belt in this model of

Hello. Yes you can replace the water pump without replacing the serpentine belt. If the belt is worn, and it breaks while you are driving, you can damage a lot of other components in that area. Typically the price of...

Q: Overheating - 2004 Jeep Grand Cherokee

Hey there. When the car is stone cold (for your safety), check the level of coolant in the radiator and plastic reservoir, too. If the coolant level is full, a typical cause of this kind of overheating is a bad...

Q: How much would it cost for battery cables under the hood?

Sorry to hear about your battery being stolen. One of our mobile mechanics can come to your location and replace your battery cables and install a new battery if you'd like. In order to provide you with a quote, we'll...

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...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...