rpm

Hi, can anyone tell me why the RPM on my 90 Accord rises. When i rev it it drops but it rises back up again. Thanks.

when u rev it drops??? and rises back up???

Hi, can anyone tell me why the RPM on my 90 Accord rises. When i rev it it drops but it rises back up again. Thanks.
yes, i've cleaned the pcv valve and the EACV but it hasn't helped.

How high are you talking about?
How high do you rev it, then how far does it drop, and then how high does it go up again?

Essentially are we talking a few hundred or a few thousand rpms...?

How high are you talking about?
How high do you rev it, then how far does it drop, and then how high does it go up again?

Essentially are we talking a few hundred or a few thousand rpms...?
it will drop to about 800 then in a few second it slowly rises to about 1200 and stays there.

Does this only happen when there is cold weather? and does your heater gauge needle stay just below the halfway mark?

Does this only happen when there is cold weather? and does your heater gauge needle stay just below the halfway mark?
It constantly happens hot or cold weather and the heater gauge needle stay below the halfway mark.

Could it just be your radiator fans turning on and off? I know the sound in my car changes when that happens, don't really look at the tach though...

Don't worry, its normal.

scubawrstlr, I think you answered the wrong question.

It fairly clearly doesn't actually have anything to do with the cooling fans.

Well it is normal for a car to go down in revs and then raise up again after reving...for instance, my Mitsu if reved will go up, then drop to like 600, then raise again to 800ish...or something like that...this is normal if the car is at optimum operating temperatures...if the car is cold, then it will tend to idle quite a bit higher, say 1200-2000.
However my Honda hasn't run in over a year, so I don't remember what the ideal idling rpm is once it reaches warm operating temperatures.

I assume 1200 is a bit high for warm temps (so assuming it still raises to 1200 once it has reached idle temps) then chances are you have some sort of vacuum leak. Check all the rubber hoses and connections, listen for air escaping while the car is idling. Also, does it stay on 1200, or does it go back and forth erratically on its own(without you reving it)?

Well it is normal for a car to go down in revs and then raise up again after reving...for instance, my Mitsu if reved will go up, then drop to like 600, then raise again to 800ish...or something like that...this is normal if the car is at optimum operating temperatures...if the car is cold, then it will tend to idle quite a bit higher, say 1200-2000.
However my Honda hasn't run in over a year, so I don't remember what the ideal idling rpm is once it reaches warm operating temperatures.

I assume 1200 is a bit high for warm temps (so assuming it still raises to 1200 once it has reached idle temps) then chances are you have some sort of vacuum leak. Check all the rubber hoses and connections, listen for air escaping while the car is idling. Also, does it stay on 1200, or does it go back and forth erratically on its own(without you reving it)?
It stays on about 1200 rpm.

My honda, when first started especially on a colder day, will start off at about 1500 rpms. Then once I hit the gas to warm it (raising the rpms), when I'm happy with reving up the motor, it will drop to 800, then gradually come to rest at about 1000-1200 rpms. As I stated before, this is normal. My car does it and so does my friend's accord (of the same generation). Don't worry about it.

My honda, when first started especially on a colder day, will start off at about 1500 rpms. Then once I hit the gas to warm it (raising the rpms), when I'm happy with reving up the motor, it will drop to 800, then gradually come to rest at about 1000-1200 rpms. As I stated before, this is normal. My car does it and so does my friend's accord (of the same generation). Don't worry about it.
Thank, you put my mind at ease.

Yeah, AccordCodger was beng an ass, I went and looked at mine- since i had it re-timed itll stop around 1500 and then sink down to 1000-1200, urs prolly just needs some timing changes if it's idling too low...