Repair Topics / Engine RPM

• Why does my engine stall?
• Why does the engine stall after replacing the battery?
• Why is my engine running rough?
• Why won't my engine crank over?
• Why does my engine have low power output?
• How an idle air controller works
• How an engine works
• How to check compression
• How to retrieve trouble codes
• How to test engine vacuum
• How to test fuel delivery system
• Engine cranks but wont start
• Engine cranks excessively
• Engine stalls
• Engine vibration
• Engine has excessive smoke
• Rapid ticking sounds when engine is cranked
• Engine has lean mixture codes
• Engine idles high
• Engine idles low
• Engine has oil leak
• Engine has coolant leak
• Engine is making excessive noises
• How to tune up your engine
• How to jump start your engine
• How to change engine oil and filter
• How does a MAF mass air flow sensor work?
• How to test an oxygen sensor

MORE: Engine runs rough questions

Question:  2001 Acura Integra mileage: 70,000. My car has no aftermarket parts on it. Recently I ran into a problem with it. When the engine rpm reaches around 3000 rpm, the engine hesitates. Then the check engine light comes on and then engine will not rev past 3000 rpm. It sounds like there is a rev limiter kicking in. This first happened on the freeway a day ago. When this happened I was forced to pull over. The engine will run in this condition below 3000 rpm with no abnormal noise or roughness. When this happened to my car, I was in the middle of nowhere. So, I was forced to drive a couple miles to a gas station. I kept below 3000 rpm. When I arrived at the gas station, I opened the hood and saw the exhaust manifold to the cat glowing orange. Unfortunately after trying several things to find the problem today, I was not able to do so. I also have a code 4, which is crank angle sensor. I have checked the crank sensor the way that All Data says to and it checked out ok. Perhaps you can help me out. This doesn't make sense to me.

Answer: The problem you described would indicate a possible partially plugged catalytic converter. Remove to replace with new and recheck system.

Question: 1997 Jaguar XJ6  mileage: 70,000.  The engine will not idle down. At an idle it speeds, the rpm's go up and down from 1000 to about 1500.  I have tried adjusting the idle speed on the auxiliary air valve this has no effect on the rpms.  I have checked for vacuum leaks cannot hear any.  Sometimes the car idles OK.  I am new at working on Jaguars.  Need help.  Thanks a lot.

Answer:  It sounds like you have a idle air control motor that has failed. Replacing the idle air control motor with new to recheck system.

Question: 2002 Acura 3.2 TL mileage: 82,000. I recently was driving my car and I was using the sport shifter, after stopping at a light, I began to drive and forgot to shift the gear to second. My car redlined at 6500 rpm, when redlining is 6300. What kind of damage did I cause if any. The car has a 3.2-liter Vtec engine.

Answer: Exceeding the "redline" by 200 Rpm probably did not cause any damage. The worst would have been some bent valves. That would cause a very rough idle and lack of power. Most engine today will not have internal engine damage do to over RPM's.

MORE: Engine runs rough questions

Repair Topics / Engine RPM