Why is my engine revving high all of a sudden?
There are three possibilities: stuck/dirty throttle plate, stuck/dirty IAC (idle air controller), or vacuum leak. If your handy and even just slightly mechanically inclined, cleaning the throttle body and IAC is an easy task with a $10 can of Sensor-Safe Throttle Body Cleaner.
How to diagnose an intermittent engine misfire?
When diagnosing intermittent misfires, don’t forget to look at pending codes for indications of an individual cylinder misfire. If your scan tool’s misfire history indicates multiple cylinder misfires, focus on the cylinder with the most misfire counts.
What causes an engine to misfire at high RPM?
>”The engine usually runs fine at idle with an occasional misfire (rarely).” This may only need a minor adjustment for timing or mixture. >”but upon acceleration at high rpm it misfires.” This would be mixture leaning out, or the spark becoming intermittent.
What should I do if I have an engine problem?
The fix: Check and replace vacuum lines as required. Possible internal engine problems. The fix: Check compression to determine engine condition. EGR valve may be stuck open. The fix: Replace EGR valve. Drive axles may be loose or worn. The fix: Check and replace CV/universal joints as required. The fuel injectors may be dirty.
There are three possibilities: stuck/dirty throttle plate, stuck/dirty IAC (idle air controller), or vacuum leak. If your handy and even just slightly mechanically inclined, cleaning the throttle body and IAC is an easy task with a $10 can of Sensor-Safe Throttle Body Cleaner.
>”The engine usually runs fine at idle with an occasional misfire (rarely).” This may only need a minor adjustment for timing or mixture. >”but upon acceleration at high rpm it misfires.” This would be mixture leaning out, or the spark becoming intermittent.
When diagnosing intermittent misfires, don’t forget to look at pending codes for indications of an individual cylinder misfire. If your scan tool’s misfire history indicates multiple cylinder misfires, focus on the cylinder with the most misfire counts.
Why does my car stall at low rpm?
The will likely force your computer to stall the engine and only allow it to run at low RPMs, which means the car will only move at slow speeds. This is a safety feature enforced by the computer so that your engine doesn’t get too damaged.
What happens when the throttle body goes bad?
Nowadays there is an electric system that’s far more efficient than the old ways but it can still have issues. When a TPS goes bad, then the car’s throttle body won’t function properly. It could either stay shut or it won’t close properly which is a severe issue. If it stays shut then your engine is not going receive air and it won’t start.
How to relearn high idle after throttle cleaning?
The idle will relearn if you put the vehicle in drive and allow the idle to come down with all accessories off for about two to three minutes. Then turn on your a/c with blower in high position for three minutes.
Why is my car revving up at the idle speed?
If your engine RPMs are bouncing up and down and your engine can’t maintain a steady idle speed then there is likely a problem with one of the components attached to your engine or a problem with one of the sensors used to keep your engine running.
Why is my engine over revving when I release the throttle?
Engine is over revving when I release the throttle. Help! My engine was working just fine last week. Then I havent rode it in one week. I made sure the petcock was closed, and choke was close before I leave my bike out for long period of time.
If your engine RPMs are bouncing up and down and your engine can’t maintain a steady idle speed then there is likely a problem with one of the components attached to your engine or a problem with one of the sensors used to keep your engine running.
Why does my car rev up when I start the car?
Thank Kevin. Common causes of high RPM excursion at start-up are typically: large vacuum leak, throttle plate stuck open, cruise control stepper motor stuck in one position; faulty throttle position sensor, and/or faulty idle air control motor or solenoid.