Help Surging idle? Options

[bdog_v]

Hi guys my 94 celica gt has been running great in these cold WI mornings of -20 below 0. But today it was 7deg above and something went wrong.

-I started it and instead of idling high for the choke setting when cold it surged around 1000 rpm. The idle went up and down about 300rpm constantly. Then when I went drive it the rpms seemed to surge in cruise control mode but not as bad without cruisecontrol going down the road.

-When coming to a stop the car would surge again at idle and sometimes feel like it was about to die then it would surge up again. So after a mile drive I quickly went home and grabbed another car so I didn't break down on the way to work.

-However I did not drive it long enough for it to fully warm up. So I will have to do that tonight to see how it reacts when warm


So I need some ideas on what this might be?

-My first thought is the O2 sensor has gone causing the car to surge,


-Does anyone know of another sensor that could cause this? Remember my high idle did not come on when cold (right after starting it cold) it just stayed low and surged around 1100 rpm to 900 rpm maybe lower?




Thanks guys I need my car back!!!!!

[bdog_v]

Well got home tonight after work and she started right up and ran like normal so who knows. I take this thing on long trips so I can't have a intermittent problem...... We'll see....

[Box]

O2 sensor wouldn't have anything to do with it. First thing is to look at the IACV, MAP sensor, and check for vacuum leaks.

This post has been edited by Box: Feb 12, 2014 - 6:18 PM

[mkernz22]

sounds like your IAC. probably needs to get cleaned out or replaced