First off its an 89 L98 (so its stil MAF, but no cold start) The motor was transplanted into a 89 factory V6 car. My issue is that it won't start unless you shoot starting fluid in the plenum. So that should mean I don't have any ignition problems right? I checked the Fuel pressure, 45 PSI When the pump primes, 35 PSI Once I fire it up and make it run. (yes both the pump and it relay work) I have had the filter replaced about a year ago, and from what I understand if I am getting those pressure readings my FPR is fine... When the car idles it is super rough, but under throttle the car runs smooth, no misses, doesn't stumble or anything... Could timing by anychance be an issue? maybe vacuum? Thanks for the help Jonny

I believe the fuel pressure is supposed to be in the 40's while running. I would look into that.

I could be a lot of things. Do you have any way to talk to the computer and get some sensor readings? Maybe TPS or IAC. Your EGR may be stuck open. These are just some guesses though.

How did you set the TPS, IAC and base timing after the transplant? All three play critical roles in your cars ability to idle properly. All 3 require specific procedures to properly set.

This sounds like an ignition timing issue. The engine will not want to cold start when the timing is advanced too far. Warm up the engine and then set the base timing to 6 degrees. The EST wire and the IAC plug must be disconnected first. After you set the timing, I would reset the minimum air and TPS... all in that order. Let me know if you need help.

well, I put the engine in this car well over a year ago and I didn't start having these problems until recent. The TPS is at .5 volts, I did set the IAC when I first put it in, we set the timing at 8. So before I can get my hands on my friends diagnostis stuff, I decided to reset the TPS, it had moved to .6 volts, and I reset the IAC. Once i did that it actually fired up but ran really low Rpms for being cold, it was like 450 rpms.
BTW EGR is deactivated in the prom...
So would a bad IAC valve actually keep it from starting?

Any ideas guys?

I have the exact same problem with my 89 L98 car. I'm doing injectors next. See my thread L98 hard starting for some excellent trouble shooting from several members.