Why does my car idle high then drop?
If the computerized engine control system is faulty, high idling can be one symptom. A vacuum leak in any of the hoses can be the culprit—inspect them all for leaks. A bad idle-speed control unit can cause the problem; it may need to be replaced. A faulty alternator can fast idle issues; if so, replace it.
What causes RPMs to drop while driving?
The engine RPM drop when changing gears is often caused by a failed throttle position sensor (TPS). If a TPS works abnormally, the air-fuel mixture will not meet the requirements. To eliminate the engine RPM drop when changing gears on VAZ cars or other cars, clean the throttle.
What happens to your car when you idle it?
When the engine idles, there will usually be a misfire that you can feel just from holding onto the steering wheel. Furthermore, the RPM of your engine will be higher than normal when the vehicle is idle. The RPM will usually go back to normal as you accelerate the vehicle, but will increase again after you stop.
What causes the engine rpm to go up when idle?
When the engine idles, there will usually be a misfire that you can feel just from holding onto the steering wheel. Furthermore, the RPM of your engine will be higher than normal when the vehicle is idling. The RPM will usually go back to normal as you accelerate the vehicle, but will increase again after you stop.
Why does my car idle with my foot on the brake?
Rough idle with foot on brake at stop light or just sitting in park in driveway runs good while driving My car has 128000 miles. My car has an automatic transmission. This may be a sign of a failing idle air control valve.
What should I do if my car overheats in idle?
Check your fan clutch if you have a mechanical cooling fan with a fan clutch. This type of fan will move, albeit with some resistance, when you turn it by hand with the engine off. Start the car and remove the radiator cap so that you can see down into the radiator. Check the water level to make it’s at or near the top of the radiator.