Help needed with 3.1 engine problem !

[618stanley]

Well I'm getting ready for cocktails for me and the project car. A crown and coke for me....... AND A MALOTOV COCKTAIL for the car !!!

The boy's "idea" is wearing me out and I need some help.
91 RS, 3.1, auto trans.
In and out of the shop, chasing a ghost folks. It ran like crap and I've been going through it.
So far with boneyard parts and parts store:
New engine control computer unit, EGR valve, MAP unit, EST Unit, Throttle Body, IAC, TPS, Fuel Filter, Plugs, dist cap, rotor. Fuel pressure reads good.
I cross referenced the boneyard parts to make sure they were compatible. Most came from a 92 firebird, with the EGR from a 91 Lumina 3.1. The EGR was a newer one and not an original 91 factory.

When this was done piece by piece it finally ran great, with the EGR & EST unit's making the difference. Just like new.. smooth and responsive... for about a week.

Towed it home at 0230 last week. It was running ok and then died. It idled ok but any pressure on the throttle..... cough and die.

In checking it out while at idle, it had a tremendous vacuum pull going on through the intake system. You could even hear the roar of the vacuum through the air intake system. I pulled the vacuum line unit off the top of the throttle body and the vacuum damn near sucked the skin off my fingers.

Next day I went back out and started it, same thing of idle ok, cough and die when any throttle pressure applied. After 3-4 of these start up episodes, it went back to normal smooth great operation, but I have not allowed him to drive it due to my safety concerns as well as $75 tow jobs.

What could be my problem guy's. Did I get a bad boneyard part and need to replace or what ? I took my time at the yard and have brains enough to decide if the part is better than average in comparison to other wrecked cars.. but I am far from perfect. I can't afford a $225 EGR at the parts store either.

You guy's are sharp out there.. what's my fix ?

Otherwise..... keep reading the paper's for the article....
" Man Burns Own Vehicle In Driveway "

Thanks,Stan

[wrightz28]

What happens to the fuel pressure during these coughing fits?

still no CEL light on?