my rpms shoot up when driving. diagnosis?

[whiskeymonkey]

Honda Civic EX 2000, purchased used 2 years ago.
75,000 miles

When driving, the engine will unexpectedly shoot up about 500 or 1000 rpms.
Sometimes I can just tap the accelerator, which causes the engine to drop back down to a normal driving rpm. Sometimes this doesn't work.

The car does NOT surge forward. The engine just revs higher than normal.

I had this diagnosed as something called an "idle valve," but this was a year ago, and I can't remember if that was the exact term. It was also from a mechanic that I later considered to be dishonest, so I never followed up on that repair. (a second diagnosis, from a different mechanic, found no such problem...)

If anyone has advice, it would be greatly appreciated.

thank you

 

[Nagasaki]

Does it only happen when moving? Auto or manual?

 

[xtingshun]

I would also like an answer to this never answered question, my friends EJ automatic w/ 114k does this as well , when going around 50=60 mph. Any ideas?

 

[Aaron.]

vacuum leak maybe

 

[xtingshun]

vacuum leak maybe

Any ideas on testing this? or troubleshooting this?

 

[Stinky]

I was thinking clutch slippage... but I may be way off base.

 

[RonJ]

I was thinking clutch slippage

That's what I was thinking too.

 

[xtingshun]

That's what I was thinking too.

I'm guessing theres no middle ground for a solution? Just replacing???

 

[Jersey8]

I would also like an answer to this never answered question, my friends EJ automatic w/ 114k does this as well , when going around 50=60 mph. Any ideas?

thank you for searching and not starting a new thread

 

[RonJ]

Do you have an auto or manual transmission?

 

[ohsnapzitzmeng]

clutch pack could but slipping in the auto also

 

[xtingshun]

Do you have an auto or manual transmission?

Its an Automatic, not my car so the details I've given are as much as I can tell you about the actual problem, but I think it's pretty well described. My first thought was something transmission area related

 

[xtingshun]

thank you for searching and not starting a new thread

I try my best.. not a total newb here.

 

[xtingshun]

Would this do this if the car was low on Automatic Transmission fluid?

 

[Jersey8]

Would this do this if the car was low on Automatic Transmission fluid?

yes. fluid level is vital for automatic trans considering it operates on fluids. try topping it off and see what happens

 

[stateofjustin]

The only thing that bothers me is you said the car does NOT accelerate when this happens. I would expect if it was a trans issue due to fluid the car would only shift into certain gears, maybe only one, or even none.

A downshift, or hunt would increase your speed.

Also, the stress that such a low fluid level would cause, the fluid would burn quickly, and you might smell the clutches as well. Check fluid quality in addition to quantity.

I don't believe you mentioned if you are able to use all the gears or not, that tells a lot on an slushbox.

I also need clarification that you can actually hear the engine increase RPM, or if you are basing it solely on what the tach is telling you.

If tach, the easiest way to test this is to temporarily install a second tachometer (carefully and properly).

Could just be an electrical issue with the console causing the tach needle to move when in reality, nothing is happening.

 

[99_EK20]

Check you air hose valves too just incase.

 

[theatre geek]

I have a question about the tranny as well. Last night driving I was going along and my rpm gauge started spiking. And this would only happen after I went anything over 1500 rpms. Thats with every gear. I can't go any faster than 42 mph and the car jumps like its trying to stall out. Any suggestions.