Sometimes when im driving along, just normal driving, suddenly my rev's start going up and down, not drastically, maybe up 300-400rpm then down 300-400rpm so then I would pull over and put it in neutral and they start jumping up and down, I mean like going from 800- 4000rpm, just up and down until I turn off my car, then sometimes even when I start it back up, it keeps doing it..! I brought it home to Honda, and they told me everthing was fine, I dont think so, if anyone has any Ideas please let me know, I think it might be my tranny (auto)..

 

exorcism

 

yah ive already checked that....
does antone else have ANY ideads??

 

My first thought would be the PCV valve. I know that when I disconnected mine to seafoam the car I got some variation in the idle. I am by no means an expert though, just figured I would throw in my 2 cents. Maybe timing, try checking that. I'm looking into trying to figure out how to check my timing right now so I can't tell you how. Sorry. GL

 

tps, or vacuum leak probably.

 

thanks for all the tips guys, I'll check the PCV valve, but I dont really know how to vacuum test it, or tps?? I dont even know what that is..!
And can anyone let me know what this seafoam stuff is, I keep hearing about it lately, and I have no clue what it is..

 

if the tachometer is jumping up and down rapidly, but the engine insn't revving up and down with the tach it would be an electrical problem. your problem would be a faulty ignition control module or an ignition coil.

 

no, no, its the engine and the tach, how do you get it vacuum tested?
And whats seafoam?

 

Check the MAP sensor also. If you aren't sure where it is at then buy a Chilton's guide from Auto Zone. Mine does this also after I accelerate and then brake. Mine isn't the sensor but I was told it was a common problem.

 

seafoam is something people use to clean the carbon buildup inside the engine, pull out the vac line and pour some in with it running

 

cool, im gonna check all that stuff, I'll let you guys know what I can figure out, thanks for all the help..