I replaced the IAC a couple of weeks ago, but I figured out that my EGR was causing problems. I ended up reinstalling my old IAC, because the one from Advanced Auto didn't work. They let me exchange it, but wouldn't refund my money, so I tried the second one, and it didn't work well either. Could they have sold me two bad ones in a row or am I missing something?

 

Did you first make sure the pintle was pushed in far enough and set minimum
air as described in the How-Tos section?

 

No, I just put it in like I've done before.

 

If the punter is out to far it will damage the iac iirc 1 1/8 extended is about as far out as it should be to avoid damage.

 

https://www.thirdgen.org/tpimod2/

 

Geez, I should have checked this out. No my parts guy is walking funny, and it's all my fault. :-)

 

Where is this posted at Tuned? I would have "assumed" it would be a sticky at the top of this TBI sub-forum, but I don't see it there.

 

Red banner at the top of your page how-tos. It’s for tpi but still applies to tbi .

 

It actually is for TBI. No idea why it has that URL??

 

Does the thirdgen tbi have a adjustable tps ?

 

Early ones do

 

I've replaced about every sensor known to man on my third gens, and they are all plug n play, at least as far as I know. I didn't look at the how tos, cause it just didn't occur to me. I mean who reads the directions? I do think it should be a sticky in both tbi, and tpi if you ask me.

 

See it everyday, and don't notice it. Thanks Tuned.

 

After the IACV is installed you jump the A to B terminals under the dash and turn the key on. Do not start it.
You will be able to hear the pintle in the IACV clicking.
Let it do that for 45 seconds.

That is the valve resetting its self.

Turn the key off and remove the jumper.

This actually should be done like this though.
In this procedure the IACV is properly reset.


"Setting Minimum Idle Speed".

1)Jump the A to B terminal under the dash in the ALDL Terminal as seen below.
2)Turn the key on but do not start it
3)You should hear a slight ticking coming from the IACV.
4)What 45 seconds then unplug the IACV with the ignition still on.
5)Disconnect the EST wire and remove the jumper.
6)Start the car.
It may be necessary to hold the throttle open slightly to prevent the engine from stalling.
Allow the engine to reach normal operating temperature.
7)Connect a tachometer. I used a digital timing gun with RPM feature.
8) Adjust the minimum idle speed using the throttle stop screw.
9) My Chilton’s says set it to 700rpm in park on an 89 TBI 5.0 auto.
10) When done shut the car off and reconnect the EST wire.
11) Plug the IACV back in.

Take it easy on the car for the first day or so.
Drive it normally on the street and highway to allow the ECM to re learn the new parameters.
The car will feel better and better as you do this.