now i get nothing... i jumped pins A & B on the aldl and waited 30 seconds, unplugged the iac connector and tried to start the car and got nothing... wont even crank

unplugged the aldl jump, put the iac back on and tried to start the car as if it was normal.... still nothing, its sitting outside dead, anyone got any ideas


its a 91 tbi

 

ok went back out after like 20 minutes.. started really hard andwouldnt idle, had to hold t he gas at 2500rpm for a while before it would settle itself out... and then it idled at like 450-500... took it for a ride and it moved up to 550ish when i got back... shut the car off and restarted it and now its back up to the 1300-1400 idle range. tried to adjust the iac again, this time it started up but went up to 2500rpm's and stayed there even with adjusting the screw on the throttle body i couldnt get it to come down with the screw all the way out... weird. so i put everything back together and restarted it and it idled roughly at about 500 so i just shut it off and i am done with it, kind of disgusted.... could it be that i have a bad IAC motor ? and maybe its stuck causing it to idle high ?

 

The wire connector that plugs right into the IAC, make sure it's connected right, LOOK at the tabs on both the IAC as well as the connector. Once I reconnected the plug 90 degrees off (yes it's possible to connect it 90 degrees off, upside down and everything) because the tabs were broke, I couldn't line it up. My idle was real high and the car barely ran.

 

yea its on the right way.... cars off the road for the winter now, so i have more time to mess with it before spring, im getting a new throttle body to try that, ive narrowed it down to i think the throttle shaft is worn and sticking in the throttle body itself... hopefuly the new throttle body cures it

 

Does the car have any error codes? Try to pull any possible codes with the paperclip method (be sure not to start the car with the pins jumped, just read the codes). If there are codes then you can try to troubleshoot them. I had a similar problem once on a 91 RS with the L03, turns out it was EGR related but I would not have known if it didnt give me the EGR code. If there are no error codes then I would go back to the basics. Check the vaccum to make sure there isn't a vaccum leak. Verify the timing is still right. I would remove the IAC and clean out the IAC passages good, be sure to set the IAC correctly when putting it back in. There's alot of info on this website but I would just do it the way the service manual says, make sure the distance between the tip of the pintle and the mounting flange is 28mm. Dirt/Grime buildup in the IAC passages can throw the idle off. After you re-install it, disconnect the battery for a few minutes to clear the codes. Then reconnect the battery, turn the car on and idle for about 5 minutes, then turn it off for 10 minutes. Let it sit, then pull the codes again. How did this problem originally happen? Was is a sudden problem or did it get worse and worse over time? Let us know what happens!!

 

i have done all that with no sucess, ive replaced the iac motor, ive gone through a whole can of carb cleaner on the tbi, and another spraying the engine bay looking for vacum leaks. the problem has gotten worse adn ive noticed lately that if its idling high when im at a stop sign or whatever and i tap the gas for a sec and let off the idle will drop, as if the throttle is sticking, so its making me believe more and more that the throttle shaft has worn itself into the throttle body and is sticking.