My 89 GTA 383 Vortec idles fine when I start it up, but when it gets warm the idle lopes from around 450-1500 and sometimes the car dies. I removed my IAC and cleaned all the passages and the IAC itself and it seems to have helped a little bit but the car still has the problem when warm. When warm it goes into closed loop? and this seems to be when the problem starts. Should I replace the IAC or what. When I tried to adjust the IAC the screw was all the way out and the car was idling at like 450. Thanks for any help guys.

 

Got a scan tool?

I have a feeling something else is going on.

 

I'm looking at an 89 code right now...

Theres a table for "Warm IAC Park Steps vs Coolant"

IS your CTS peachy?

 

Not quite sure how to check the CTS. I think I am just gonna replace the CTS and the IAC and see what I get. I knew the RPM hinged on coolant temp so when the car switched into open loop that is when the problem started. Thanks for the help. Also for your scan tool question, I am going to buy chip burning software and I have a laptop, so what should I buy that will help me scan what is going on with the car.

 

www.wotelectronics.com

You can get a cable from steve ruse for your laptop, couple that with craig moates FREE (thanks craig :rockon: ) software and you can find out what your CTS is reading for temp and compair it to your dash gauge.

 

Wow that ****in rocks!!!:rockon: Thanks for the help man.

 

Whats the difference between his cables and the cables made from the Diagrams on Craig's site?

~M~

 

You have to make the ones from the diagram on craigs site


Some people would rather cut to the chace and buy one.

 

Guess I should have said; "beyond the obvious" what's the difference...So they are the same cables then...ok
Making my own should be easy enough.

~M~

 

Yes same cable.

In fact steve will sell you kits so you can make your own, only buying the parts from him. Cuts down on time searching for them.

 

Already found all the parts I need here, http://www.mouser.com/
and at good prices too. Just wish there was a place to get OBD I connectors, guess I'll see about molding my own.

~M~

 

Steve kinda haves them


They were sorta cheesie and boxy...

But they certainly work

 

I have downloaded the software from craig so if I bought the 65 dollar cable from wotelelectronics, I would be ready to rock? Do you know if I buy the 45 dollar cable, does it come with instructions. My uncle has been an electrician for like 30 years so he should be able to put the stuff together. Thanks I am finally gonna get into tuning and burning my own chips and I am excited

 

Just to cover all bases.....

You do know thats just how to make a scanner right?


To burn you still gotta buy a burner.

However, yet again the software is free

 

Yeah I know that's just a scanner but after i get the ability to scan the car I will buy the stuff to burn. Also, i could buy the full assembled cable for 65 and this would be the cable I need? The one for OBD1 cars? Thanks again

 

Yup thats the one


You can always double/tripple check with steve ruse, he's informative enough and doesn't mind answering a few questions.

 

It's gonna be pretty cool to be able to check these sensors for sure instead of judging by symptoms and then replacing what "should" be the problem. Craig's software looks pretty nice and I will eventually buy something a little better. Thanks