Q: RPM fluctuation, engine shuts off at the traffic light

asked by on

Hi. I have a few problems with my BMW. I had the worn fan belt replaced. I installed a new water pump along with the pulley. The issue is with the revving that seems to fluctuate a lot now. While I'm sitting in the car and not moving for a while, like at the red light, it would sometimes shut off. The steering is hard to turn as well. The engine doesn't seem to be overheated. Also, there are no leaks as far as I can see. Do you have any idea how I can fix this? Thanks.

You may have a belt tensioner not suppling enough tension on the belt. The power steering may also be low on fluid. The belt may be loose which will need to be adjusted tighter.

The idle problem may be due to the intake hose from the air filter to the throttle body. It may have a leak or is not sealed well, causing an air leak and the running issue. Have a certified mechanic diagnose your stalling symptoms and scan the computer for codes. Once this is done, a proper repair can be made.

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. RPM fluctuation, engine shuts off at the traffic light

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: Front brake gets locked up - 1983 Jeep CJ7

Have the residual pressure valve for the locking brake checked for problems. Residual pressure valves maintain a very slight hydraulic pressure for each brake in order to make the brakes more responsive when you press the brake pedal. If it...

Q: Q: Leaking at water pump

Hello. If you had a sudden loss of engine oil and then the engine stopped running then you may have an engine failure. If the engine loses enough oil, then it can not longer lubricate the engine and it will...

Q: Car just spins over but wont crank 1999 BMW 323i

Hello - your failure scenario description suggests a blown headgasket, especially with a history of overheating. I would have the compression checked first, and suspect it will be low on most cylinders. It is also possible that the timing belt...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
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...
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...