[Integrity_96]

Hey guys, maybe you can offer some assistance on this for me please. I got a 96 LS teg with a full B20 engine in it with some bolt on mods. When the engine is cold, I'll start it up & the idle will go up to 2000rpm & then drop to 1600rpm & then back to up 2000rpm. It just keeps doing that bouncing around stuff till the engine warms up, then it will drop to 900 & stay steady there. It has never bounced like that before till about a week ago. Anyone know what may be causing this?

I already know that my front O2 sensor is going out cause my Air/Fuel gauge is spiking alot, but that has been happening for a while now & has never affected the idle, so I know it's not that.

 

[randyman]

it might be time to replace either ur IAC valve or the fast idle valve. check ur coolant level first if it's empty or not. if it is full then it might be the thermostat. if not, it might be the IAC. or the fast idle valve. check out ur service manual to properly check the IAC and fast idle valve and the rest of the troubleshooting.

 

[batboyx]

Integrity, that's happening to me too. The summer is getting away and the cool air is hitting me and it's been idling high until i rev a few times and drive 2-5 miles. Anyone know what's up? What's IAC?

 

[randyman]

Integrity, that's happening to me too. The summer is getting away and the cool air is hitting me and it's been idling high until i rev a few times and drive 2-5 miles. Anyone know what's up? What's IAC?

Idle Air Control valve. it's bolted onto the side of the intake manifold facing the firewall.

 

[phi67]

there could also be air bubbles in your coolant lines. that happened to my car the first 3 days after i put in my new engine. after we bled the coolant lines, it idled normal.

 

[drpepper962]

on my friends civic it does this i forgot what he said i was wrong i will ask him i am sure its the same thing

 

[Integrity_96]

Randy,

I don't think I'm gonna have that IAC you are talking about. I don't have the stock Intake Manifold anymore. I have a Skunk II ITM & I haven't seen anything like what you are describing on the side of it. Here is a picture of my ITM, am I overlooking something?