92 Blazer 350 Rebuilt TBI put in new IAC stalling issue

[DickC]

this is not the vehicle in my signature. its a bone stock 92 full size blazer(2 door Tahoe) 350 tbi. before I did anything the truck would idle but when placed in gear would stall most times unless I blip the throttle. sometimes would stall when stopping/turning into drive way.. so I rebuilt the throttle body did the mod of grinding down the whatever tabs for more airflow. cleaned re assembled reinstalled along with new IAC. at first I didn't do the IAC reset but the Haynes said 10 sec key on then 10 sec off the run for 5 minutes. then 30 sec off and restart. well about 4min30sec in idle came down to about 1000 then dropped off surged a couple times then stalled. disconnected battery reset the disconnected IAC started from beginning still having same issues. vehicle doesn't even come up to temp. replaced cap rotor and plugs less than 100 miles ago. other than lighting on fire in drive way any suggesions ?

 

[c1500deathtrap]

Donate to nearest military firing range. My preferred range is BT-11 by camp Lejuene. Warheads on Foreheads.

 

[DickC]

Donate to nearest military firing range. My preferred range is BT-11 by camp Lejuene. Warheads on Foreheads.

I'm on bragg so that's definitely an option but I prefer to get it running right

 

[chipskittles]

Did you check for play in the throttle shaft when you did the rebuild? Long ago I had a 92 Camaro that had this issue, never did figure it out.

 

[DerekTheGreat]

What is the base idle? You need to the ALDL ground out thing (Its on the internets somewhere) to get the IAC to close. When it's closed, unplug it and then start the engine. Using something reputable (not the truck's tach) adjust the RPM so that it's ~450. Should be like a T20 or T25 bit near the throttle linkage and it may have a cover if no one messed with it, but after a rebuild it may need to be messed with. Of course, you could just keep upping the idle by turning it clockwise to see if it helps any without doing the official procedure. That's what I initially did with our '88 TBI 454 just to see if that's what it was and well, it was so I ended up doing it the right way later.