Strange Idle Surge

[TurboLaserRS]

I've read Terrys idle surge thread. What it contains doesn't really apply to my situation. When I first start my car up, it runs just fine. Everything is normal for about 3.5 to 4 minutes until its nearing operating range. Then it starts surging. If you drive it for awhile, it stops surging but idles over 2k rpm. This only happens when the temperature has fallen below say 45 degrees out.

Awhile back, I had a coolant leak from the throttlebody, so I just looped the lines together. Could this surge be caused by the FIAV because it's not melting that wax pellet in there, and its cold out?
I also have a fried ISC, and have not replaced it because they are 3/4ths of what I paid for the car. I just leave it unplugged, and have honestly never had a problem until now. I think it has to do with the temperature. Would the 'free block off' method for the FIAV benefit me at this point? I'm thinking about trying it, along with replacing whatever gasket leaked out on me.

 

[92AWDHX40]

Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)

 

[TurboLaserRS]

I've read Terrys idle surge thread. What it contains doesn't really apply to my situation.

Wow.
The FIAV is the only thing I can think of. The ISC not being hooked up has never made a difference in the past 6 months of driving daily.

 

[jakk220]

Checked for vac leaks?

 

[TurboLaserRS]

This thread is resolved. I took the throttle-body off, and screwed the FIAV all the way in until it bottomed out. Put everything back together and no more idle surge! My guess is that the car would get up to operating temperature, and the FIAV was still wide open so the ECU kept dumping fuel since there was more air than there should be which = my erratic idle. It was in the 20's degrees out tonight and it did take the car dying once. The car runs like poo at about 300rpm if you don't give it a little throttle for about 30 seconds or so and then it's fine! Hope this helps someone.

 

[undefined0000]

That's good! Never heard of that before. Toledo, nice! Closest Ohioian I've run into on these forums .