after driving my si for like a hour or more my idle will start to jump from like 700 rpm to 1,500 rpm... its only after driving it for an extended period of time... it doesn't stall or anything it just drives me nuts and makes me look like an *** at stoplights. it did it before i got my cam and what not... has anyone else experienced this and figured out what causes it? i have no friggin clue and it drives me nuts

 

i would like to know too! mine does that also! and i just did a tune up!

 

my tach used to be CRAZY! my rpm's were everywhere and my idle sometimes went down to ZERO(but never stalled) it turned out to be a loose wire... i re-soldered them back together and its been running perfectly ever since. So, check all your wires.

 

no my tach is right... the engine revs up and down... kinda like between cold idle and hot idle area...

 

mine does the same thing, I think it's a vacuum problem. I know my lines are messed but I don't know how to fix them.

 

maybe... but i dunno... a vaccum line generally sucks all the time... not just after so long... i guess one of these days i could go and check em all over

 

Vacuum line prolly. Throwing any codes or do you get a CEL ???????/ check your ECU when it acts up on you. Very weird. Should idle screwy all the time if its a vacum leak. Fuel filters maybe. When your tank gets low...........

 

ok listen up.. this use to be a long thread before and I was so frustrated about this issue when I had it. First thing I did was the EAVC sensor which is behind your intake manifold that didn't work, but people tried replcing it and they actually fix their problem, next the TP sensor they told me to replace it but no luck on my side. Finally,! after spending my money getting it check twice by some proffesional shop and still no answer a Honda Guru has an answer. There was a leak between my intake manifold and my cylinder head. don't ask me how but it sure did fix it and that's it. So goodluck to your problem.

 

Ahhh yes i remeber that thread... So i guees you better check all your gaskets inculding taking off your intake manifold gasket etc. pain but you gotta do it or pay 40 bucks a hour to get fixed.

 

mmine was doin the same thing after changing motors. i asked my uncle about it. and he told me it was a vacuum leak. turns out it was now it runs fine. so might be a vacuum line off or in the wrong place.

 

your thurmostat is fuct buy a new one $14 k 9 times out of 10 if your **** idles all stupid its thurmostat


[Modified by TorteX, 11:58 PM 4/8/2002]

 

thats interesting... but wouldn't a gasket leak there me more evident... like hear and feel the air escaping or being sucked in? i'll look into that... i highly doubt the thermostat is cause the problem... seeing as how i don't over heat or run to cold its working just peachy... i have no cel and my ecu is free from codes

 

so you are telling me I can get a thermostat for only 14,000 dollars what a great deal. Can you tell me where they are selling them I might have to buy two of them at that cheap of a price.

 

Jeef, I had the same exact problem with my car...and I still have no idea what causes it...I know what you mean about feeling like an idiot when your car is idling at 1500 @ a stoplight, for no reason...

In my experience I've...
1) changed the thermostat - that didn't work...it only stopped my car from overheating
2) checked the EACV screen to make sure it wasn't dirty - that didn't work...cause my EACV DOESN'T even HAVE a screen for some stupid reason!
3) eliminated all ecu codes - that didn't work
4) flushed my radiator fluid (in case there were any air pockets) - that didn't work
5) yelled and cursed at my car - that didn't work... but i sure felt better

From what people have told me, I should also try to
1) clean the throttle body
2) (can't think of the rest...i'll edit my post once i remember them)

Jeef I also agree with you on the fact that it probably would be the vacuum lines or a bad gasket since this would cause the idle to be constantly erratic...from what i understand both our cars have an erratic idle driving for a while...for some reason, my idle is very erratic when the whether is warm/hot outside...this thing is still a mystery to me ...hope some of this info is useful in some way...


[Modified by 606zc, 10:57 AM 4/9/2002]

 

i just changed the o2 not too long ago... hmmm one of these days i'll break down and get a bigger bore tb and clean every thing up replace all the gaskets on the intake side... the exhaust was already done with the header... jeesh at least i know i'm not alone on this one though

 

i also have a problem with the car idling at 1500rpm when warming up