Got a tremendous idle problem, right after i start and the ecu ends its "open loop" per say it bounces idle like crazy even when im driving for a while, and sometimes it'll be perfect. but most of the time it would have a bounce to about 2500.

When i hit the clutch to shift i can tell its reving without the gas it sucks and super annoying anyone got any suggestions or had this problem?

 

throwing any codes??

 

Negative only code is vss speed sensor. the idle is soooo annoying. cause when im at a light everyone thinks i want to race them LOL, then i see them take off then i spank them a mintue after i notice it.

 

in the services were you?? jk i had a similar prob in my 91 lx and i was told the iacv (idle air control vavle) was bad. dont know if that was it cause i sold it without fixing it. but it gives you something to check out

 

Bump, yeah I'm in the Air National Guard actually hehe yeah a friend thinks its a coolant problem but temp is prefect. Anyone else got similar problems with different cures?

 

surging idle is commonly the cause of a vaccum leak. but it should do it all the time. not just once the o2 is reading.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99b18 &raquo;</TD></TR><TR><TD CLASS="quote">surging idle is commonly the cause of a vaccum leak. but it should do it all the time. not just once the o2 is reading.</TD></TR></TABLE>

Not true. Think of a condition, on a perfectly running, no-vaccum leak engine, where the instant you start the car, the idle is raised by the ECU??

Yep - cold start. So really, a vaccum leak is going to cause surge when the ECU thinks the engine has now warmed up - not when its cold.

Air bubbles in the coolant will also trick the ECT into thinking the coolant is cooler than what it is - this tells the ECU to re-activate the cold-start-up strategy and increase the idle till it thinks the engine warms up.

But with an idle rpm of 2500 - you are more than likely looking at a vaccum leak and not so much air in the coolant (but bleed it anyway to make sure - doesn't take but 10 minutes or so).

 

IACV

 

Yea, I had similiar problems and changed alot of things to try to find out what the problem was. it's either a vacumm leak, IACV, or your throttle body itself. I found out it was my bored out tb, no idea how..must be a leak at the butterfly. Mines jump from 1000-2000 back n forth and sure is freaking annoying. i even had a few morons rev'd at me because of it.

 

thanks for the great feed back, luckily i need a good tune up on the car, so im gonna replace all the radiator hosing anyways, cause i found a tiny leak on the feed hose, and im gonna check the control valve.

Thanks alot guys

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kihun_cha &raquo;</TD></TR><TR><TD CLASS="quote">IACV</TD></TR></TABLE>

try unplugging it and see if it goes away. also, make sure your cooling system is well bled.