Q: The car revs while not moving, the check engine light is on

asked by on

The check engine light is on, on the Head-up Display of my car. It revs up and down when the car is not moving. I checked the cylinders as I was told at the dealership that if they misfire, this can happed. I checked that out and the same problem happened. I also had the transmission fluid changed but to no avail. I took it to the shop again and they told me it is the intake manifold causing this. I would like some advice and another opinion about the cause of this issue. Thank you.

Hello. If the engine speed is going up and down as the vehicle is sitting there and running, then it is not a transmission problem. It can be an intake manifold issue as they mentioned, as I have seen a lot of these fail and cause this. Most of the time though, it is caused by a faulty air flow sensor. When this is not reading right, then the computer cannot control the idle. I would scan the computer for codes to see for sure what the computer is seeing. If you are going to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose your Check Engine Light and proceed with appropriate repairs.

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 while not moving, the check engine light is on

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: Q: Can I change the transmission fluid

Hi, thanks for writing in. That "debris" you feel is usually clutch material. Clutch material inside automatic transmissions is very similar to manual transmission clutch material as well as brake pad material. It generally appears as a fine dust. While...

Q: If cylinder 3 misfires is that a bad thing?

Hi there. A misfiring cylinder can be expensive if allowed to continue. The catalytic converter can be damaged. If the cylinder is misfiring, the coil, wire, and/or spark plug could be the cause. First swap the spark plug between cylinder...

Q: Flames coming from the tailpipe and rough idle

Hello there, many common faults will cause your 1984 Dodge D250 to have a rough engine idle and have flames coming from the exhaust. When flames are seen coming form the exhaust it is most often due to unburnt fuel...

Related articles

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...
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...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.