Need help with 3rd gen firebird

[Dharris89]

I need some help with something I just found. My car is a 1989 Firebird Formula with the 350 TPI motor. It’s had an issue for the last few years where after it runs for a while it shuts down and won’t restart until it’s cooled off for at least a day. I’ve replaced most of the fuel and ignition parts. I just got it out of storage and saw what looks like a very burnt connection. It’s back near the firewall on the passenger side. One part has a black, dark green and light green wire. The other only has a black and dark green. Anyone know what this connection is and if there should be 3 wires on both sides? I’m hoping this has been the issue but not sure why it would do it. Thanks.

http://www.columbusracing.com/forums/picture.php?albumid=1007&pictureid=9407

http://www.columbusracing.com/forums/picture.php?albumid=1007&pictureid=9408

http://www.columbusracing.com/forums/picture.php?albumid=1007&pictureid=9410

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[Dammit Charlie]

What's it run to and from? None the less its toast and needs fixed.

[Gergwheel1647545492]

Not sure if this helps, but here are the wiring diagrams for your car.

 

http://www.columbusracing.com/forums/picture.php?albumid=1054&pictureid=9423

http://www.columbusracing.com/forums/picture.php?albumid=1054&pictureid=9424

[Buck531]

Not sure that's actually burnt. On the Fiero my connections look like that that go to the body and wiring harness. It's some sticky weather pack material GM used back in the 80's to keep from the connections from corroding. I've been told not to clean that off.

[Dharris89]

Not sure that's actually burnt. On the Fiero my connections look like that that go to the body and wiring harness. It's some sticky weather pack material GM used back in the 80's to keep from the connections from corroding. I've been told not to clean that off.

 

Buck and Greg thank you. I went to the junk yards for research and I saw some other GM cars with the same “goey” connection. I thought it got hot enough it melted and was like that but I guess not. I’m still not sure what it does but at least it probably isn’t my issue. Still can’t figure out why it will barely run.

[excell]

Have you pulled codes on it?

[Dharris89]

It’s an 89 so the the computer is the old plug in the key and count the flashes. The check engine light isn’t on but when I check, it flashes code 12 which is ok and code 34 which is MAF or MAP. But the light is not on. My car doesn’t have a MAP sensor. I have another MAF somewhere in my parts bins but I don’t think it’s that unless it’s a new issue. Last week was the first time I’ve had it out this year and it won’t run without part throttle. I adjusted the adjustable fuel pressure regulator and it sort of idles but still runs like garbage. I need a fuel pressure gauge to go much farther.

[Dharris89]

Historically it has run really good for a while but after an hour or so it slowly dies and won’t run again for a day or so. I’ve replaced the fuel pump, fuel filter, fuel injectors, adjustable furl pressure regulator, O2 sensor, fan sensor, ecm fan sensor, coolant temp sensor, ECM, MAF (I think), coil, wires and the entire distributor including the ignition module. I’m just really stumped and frustrated. Electrical certainty isn’t my forte and that’s probably where it is. Thanks

[Buck531]

Not sure on that year/OBD1 but will it run if you unplug the MAF sensor?

[Geeto67]

LS swap it. no tpi...no problem. J/K

 

Check the MAF (and TPS), but to me it sounds like a fuel pressure regulator issue. I had a dodge van that has similar symptoms and it turned out to be both a vacuum leak and a hole in the diaphragm for the pressure regulator. at low speed the thing was dumping fuel into the engine so it would try to stall, would only run at mid throttle, and then if you ran it for an hour on the highway it would cut out and die from fuel starvation. wait 5 min, prime the pump, and it would take off and run for another hour before dying again.