Truck runs great, except the high idle. It idles fine when warming up, but once I drive it and push in the clutch it idles at around 1,500rpms. I don't have my tach mod finished, but it seems to be around there. I went through the plenum and made sure it wasn't a vacuum line. though I haven't quite ruled them all out yet. What would make it idle so high??

Another issue i have run into. I can't get a OB2 reader to work with my harness. Anyone know the correct wiring for a reader? if anyone thinks they can help, I will post what my OB2 scanner port is wired like.

I have a feeling some of my power is being robbed via a sensor that has gone bad, but i have no way of scanning the trucks system.

 

Recently did a swap and needed to pull the iac and clean it. It was stuck with carbon buildup.
Idled about 1600 before and about 750 after. Fairly straight forward but there are some good write ups in the 96-2002 forums here.

 

When I finished my 3.4 swap, mine idled high too. Had to swap the Idle control valve, old one was bad.

 

where does the vacuum line with the red cap go to? I think this is part of my idle issue. I have this tube capped off. Any Ideas?

 

that goes to the evap vsv

right here. The bigger hose that is off is the one with the red cap in your picture

 

is your throttle cable adjusted right? even if the the throttle plate is opened slightly it can throw everything off. try wiggling the cable while the engine is running at idle. if you hear any difference in idle chances are the cable is adjusted too tight

 

just take the throttle cable off and see if that cures the high idle. If not, leave it off as you find your demon

 

It also tends to pulsate when the rpms drop or if I push in the clutch. Any idea if that has something to do with it? It also feels like it has a slight bog before 3500-4000rpm and then it gets a surge of power.

1. My timing could be off.
2. I think I have a leak between exhaust manifolds and crossover


Could the fact that I have a exhaust leak before O2 sensor make the engine run crappy? possibly O2 sensor making the car run funky? When I wired up my O2 sensor I had two black wires, I had a hard time figuring which one went with what wire.

I have no EVAP setup at all. I have all the components; VPS vsv and sensor as well as the 3.0 VSV. But since I have a 2001 5vz, i am having a hard time figuring out the vaccum line routing since most of you guys have done pre 2001 swaps. I am using the old 3.0 charcoal canister.


Anyways, I am headed out to the geerage to try a few things. Thanks for the help so far, it is much appreciated!

 

IACV valve was stuck. Problem solved. Thanks