Need help! 95 gst problems.

[Diamond Star Werks]

ok so got a 95 gst that i just rebuilt the engine in. Everything in the engine is brand new besides crank, rods, and the rocker rollers. New crank sensor and cam sensor. Changed the maf with another one i had, changed the map sensor, tried another computer. I've looked at it a ton and my dad's partner who owns a mechanic shop who built and installed the engine for me looked at it for awhile. We've found nothing that has helped fix the problem. I'm fixing to find and go over all the grounds i can find and see if it is just a bad ground. Ok now for the problem. From cold car starts up and runs great very strong. It doesn't surge or skip or act up at all. It revs up and idles good. It can drive good too real strong. Warms up changes from open to closed loop without messing up at all. So pretty much there are no signs of any problems at all before it starts to act up. Now as said it warms up open loop closed loop fine no signs of any problems at ALL. But then after a lil bit (sometimes a few min longer than other times) the car will either act up a lil misfire and then cut off or it will just shut off like i turned the switch off. Then i can start it up (sometimes) and it will crank then cut right off and i can give it some gas i can keep it from cutting off for A short time but eventually it will shut off and not start and have to sit for awhile before it starts again. Now if i rev it to keep from cutting off the whole time is acting up misfiring and backfiring allot. Then eventually it will cut off and not start again. Idk what the hect is happening with it. It isn't throwing any codes either. I'm using the Snap-on Verus scanner on obd direct(because the mitsu connector is missing??) and maf, map sensor, IAT, 02s, fuel trim is all reading correctly and nothing goes on the fritz when it acts up. Only mods are greddy turbo timer+intercooler (not fmic), and one piece exhaust. And an act clutch but thats out of the equation anyways. If anyone has any ideas I would greatly appreciate it. Thanks in advance.

 

[Fenix22]

Can you see if it's leaning out while the problem is happening? Sounds similar to a problem I had which replacing the pcv valve seems to have fixed.. Apparently it was getting stuck open & cause a massive vacuum leak until it was able to close.

 

[NordicSaab]

It certainly sounds like some kind of a/f metering issue which would typically mean a 02 sensor or a MAP sensor... but if it is not throwing any codes... ???

Kinda left field but when is the last time you had the fuel injectors services... I had a saab with a similar problem and on the the fuel injectors was not functioning properly and the metering could not compensate for the faulty injector. Could also explain the not starting if the engine is flooding.

 

[Diamond Star Werks]

Yes I had a a\f gauge in it a few hours ago thats before i ripped it out with the rest of the crappy wiring that one of the previous owners had done. I took the ground for the a\f gauge and touched it to the positive terminal and it would click the mfi relay?? and it would ground out the temp gauge but when i would have the key on it would instead of making the tempp gauge go super cold it would go super hot. I started seeing stupid ppl when i saw all that. So i took out all wiring that whoever had done with the exception of the turbo timer which seemed to be wired correctly. After removing all that wiring i started up let it run but still same problem. So just to check i plugged in another computer but still same result. So pretty much i figured it could only be one thing. A defective crank sensor. I had already tested the cam sensor earlier when the car would not start and it was reading properly. So i closed up shop and took a bunch of tools and stuff down to my junkyard where I had another gs-turbo eclipse with a busted block and quickly yanked off both cam and crank sensors. The cam sensor had a broken ear and ### the other was reading right i decided to just swap crank sensors. plus i didn't want to take the timing belt off which you have to do to change the cam sensor but not the crank sensor ### you can pull the crank sprocket out because it isn't pressed on off course and you can take the nut off the oil pump pulley and twist the belt just a lil which allows the crank sensor to slip out without removing the t-belt. So anyways swapped crank sensor and put it all back together and it seems to have finally solved my problem. It has warmed up and been running for long enough to cut the cooling fan on and off several times now and is running pretty steady right now so hopes are high that the problem was a defective 70$ crank sensor and has been solved. I wasn't going home till this dang car was fixed! Thanks for the tries to help out.