OK PLEASE HELP IM A FORD TECH NOT TO GOOD WITH THESE OLD VETTES I HAVE A 90 VETTE IF IT SITS OVER NIGHT IT STARTS & RUNS FINE FOR ABOUT FIVE MINUTES THEN I LOOSE INJECTORS & IT WONT RUN AFTER THAT I HAVE REPLACED THE COOLANT SENSOR MAP & FUEL PUMP I BOUGHT A USED ECM IT DOSE THE SAME THING HELP PLEASE COULD THE PROM DO THIS ?? THANKS IT DOSNT LOOSE SPARK

 

fuel, air, spark

start with the basics, and go from there. check fuel pressure. jump the terminal and check for codes...i bet you have some.

 

THANKS FOR THE REPLY BUT I THINK I HAVE COVERED THE BASICS THEIR ARE NO CODES IM LOOSING INJECTOR PULSE COULD THE PROM CAUSE THIS THANKS

 

When you loose pulse, check to see if you have 12v on one side of the injector connector. The ECM grounds the injectors to control pulse. There are 2 injector fuses, left bank, right bank. Won't be a problem with fuses unless there is a connection problem, because the car restarts eventually. Prom could be the prob, but not likely because usually they are either not working or are working -- not intermittant. You might have an injector shorting out and when that happens, the ECM shuts down the quad drivers built into itself for protection. Ohm check them, should be around 15 ohms with no more than .5 ohm variance. See if you have no pulse on both banks when it quits. Good luck. [8D]

 

THANKS I NEVER LOSE MY 12V BUT AS FOR ONE BEING SHORTED I HAVENT CHECKED I THINK YOU MIGHT BE ON TO SOMTHING THANKS!!

 

THANKS MECH259 IT WAS A INJECTOR SHORTED OUT THANKS AGAIN

 

Glad I could help. That happens a lot @ my shop. We replace several injectors a year. [8D]