Check to see if dirty or carbon build up on iac, clean and see if it helps. Might need some top engine cleaner, sea foam or another brand. I have used sea foam on my cars in past but I am sure others have their products of choice.
Good luck and nice wagon.

 

Thanks! Definitley need to run seafoam, but I dont know the best way on this TBI setup. Can you help point me in the right direction?

They make a new spray can with a special nozzle to insert in the Throttle Body, but I dont think it will work with this setup (to be honest, I havent gotten far enough to even pull out the air cleaner assembly to see what the setup looks like!)

 

There should be a vacuum line running from the rear of the intake manifold to the brake booster mounted on the firewall. Unplug that vacuum line from the firewall and run it through there.

 

On 87 Buick wagon I had car running and sprayed into throttle body a little at a time until engine would start to cut off but I have also taken off of car and cleaned. Been a long time since I did this hopefully some of the others will suggest other ways.
Always good to have choices.

See thanks CE

 

Thanks again fellas.

On another note, so bummed because I HAD an O2 sensor lying around from my 90 Olds Trofeo that wouldve worked on this car, but cant find it anywhere! ARGH!