Why do my Revs go up and down at idle?
Say the car idles normally at approx 700/800rpm. All of a sudden however, the revs will drop down to 500 and the car shudders, revs jump back up to the normal idle, then drop back down to the 500, then jump back upto normal idle. It seems to happen randomly, but a sure way to induce it would be to have the A/C turned on when approaching a stop.
Why does my RPM drop when sitting idle at traffic lights?
While I’m sitting idle at traffic lights I put the car into neutral. The engine stays idling at about 1000 RPM. However every now and then it drops down to about 500 RPM and then quickly back up to about 1200 then goes slowly down to 1000 and stays there for a bit until I go again or it drops again.
How does the idle speed of a car work?
This valve is controlled by the vehicle’s computer which will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed.
Why does my car rev up and down?
Since your car is idling up and down, this may suggest that it may be receiving incorrect voltage causing it to fluctuate erratically. I would recommend having an expert from YourMechanic come to your location to diagnose and repair your idle air control valve. Was this answer helpful? Thank you for your feedback! Sorry about that.
Say the car idles normally at approx 700/800rpm. All of a sudden however, the revs will drop down to 500 and the car shudders, revs jump back up to the normal idle, then drop back down to the 500, then jump back upto normal idle. It seems to happen randomly, but a sure way to induce it would be to have the A/C turned on when approaching a 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.
How often does Honda engine rev at red light?
I have a 1990 manual Honda Civic with ~200k miles. When I’m stopped at a red light, the engine revs up to about 2k-3k rpm and then down to 1k rpm. This cycle repeats about once every two seconds.
What does a flashing engine management light mean?
A flashing or continuous warning light can show If the ECU calculates that the engine isn’t quite running right. An EML – usually presented to depict a stylised engine block, but sometimes taking the form of a ‘check engine’ message – will illuminate as a prompt to seek further assistance.