ok.. this is a weird one..
Sometimes, while driving along at a constant speed i feel the engine start to rev up a little bid on its own, then, when i put the clutch in the engine will continue to rev (all by itself) to about 3500rpm and it will stay there. It will rev smoothly and evenly (not erratically). When it does this, i give it a little tap on the pedal and rev myself, it and then it drops back down immediately.

The motor is a stock sohc.. its my daily driver.. normally any type of erratic idle in a honda usually points to a leaky throttle body gasket or a tps sensor.. but this is really really odd... it never did it before.. and now it has done it approximately three times during the course of one week (under daily driving). Im not really sweating it because it doesnt seem to be a real issue.. but its really making me curious..
what do you guys think?
Intermittent problems like this are always a pain in the *** to troubleshoot.

 

Sticking throttle?

 

I dont feel that though.. i had a car do that once.. and you could feel that little tick when it catches. but not to mention, it revs UP. If the throttle stuck, it would just pause for a second.. it wouldnt rev up gradually to a point and then hold like it is



Modified by twelvesorbetter at 9:43 PM 1/19/2006

 

if its revvin up steadily without you pushing the throttle, the only thing that can cause this is an air leak situation.
ILoveJDM is right, a sticky throttle that sits open will rev up, not cause a pause. take a look at the throttle body, see if it needs a cleaning/lube. also try blocking off all unneccesary vaccum lines (ie cruise, etc.), as these might be the source of the air leak.
good luck

 

it revs only to a point and then stops and holds steady.. which is characteristic of an air leak, yes-

BUT

When i do goose it, it seems to 'snap out of it'.. whatever its doing. THIS is why i find it so odd... if it were an air leak, it would not be corrected by my goosing the gas pedal.. it would just continue to hold steady at whatever rpm and when i rev'd it, it would only drop back to that rpm.

vaccum leaks or a back tb gasket are the obvious things.. and im almost positive its noth either of those...

 

Check the butterfly mechanism in the throttle body. Sometimes if can get slightly held open from dirt, corrosion, etc. and not close 100%, which would explain the RPM's raising and staying steady. When you slap on the throttle it goes down due to the butterfly being forced close for the spring pressure. Make sure your throttle cable is adjusted properly as well.

 

possibly a malfuctioning (IAC)idle air controller??????

 

IAC would likely cause the car to stahl and not idle at all...
I think im more inclined to believe what the poster above said.. the butterfly valve is not releasing because it may have some dirt on it and is sticking in place when i ease off the throttle.. im going to look into that tomorrow.. it had no air filter on it for a short period of time..and that would make perfect sense.