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Hello, I am working on a 91 lumina 3.1 auto.

Here is the problem

It will start and run for about a min then die.

So i hooked up my fuel psi gauge,timming light to watch spark and a NOID light to watch for injector pulses.

it will start and run about a min then die, but after 3 or 4 runs it will not start up again..

its getting spark the hole time

getting about 39-42 PSI of fuel.I even changed the relays

the noid light flashed when running and being cranked untill it stops running and will not flash again even while being cranked..

so i thought the ECM was the problem, got a re-man one and opon opening the box i noticed a torn CORE tag.. I new it was a new one cuz i opened it at the store.
anyway it looked new, but i called the store and tey said i could return it but they didnt have anymore..

I tried the reman ecu and still nothing.. so now im wondering if it was bad, or the e-prom is bad?

what else can cause the inj circut not to pulse..

the car will run if i use carb cleaner in the TB and ot one pulse from the noid light.  

autozone covers a lot of stuff on this car...
but you really should print this diagram out...

http://repairguide.autozone.com/znetrgs/repair_guide_content/en_us/images/0900c152/80/06/7e/6a/large/0900c15280067e6a.gif

it explains what sensor readings should be displayed  when you plug in a scan tool...

with a scan tool... you can see if you have good crank signal sensor signal .. and good .. cam sensor signal...  
i would really look at the crank and cam sensors..


you also need to check the coolant temp sensor voltage.. as displayed with a scan tool...

the modules can be removed and tested at most autozones... i take it that this is the motor with the 3 coil packs on top of the module...

i dont remember .. how the ecm gets the timing to cycle the injectors...  probably through the module...  so the module might still be firing the coils.. but not sending info to the ecm for the injectors..


have you gotten any codes.?????  if the cal pack or prom is bad.. you will get codes for them..

do you have a scan tool that will plug into the early gm system???  really makes life simple... and i am talking about a scan tool... not a code reader...  compare all the sensor readings with the above chart...  

post any differences... you find..