1G ecu swap question EPROM to no EPROM

[superrandomguy]

i have a 1990 gsx and i had a ---902 eeprom ecu and it had leaky caps and fried the board beyond repair.

I purchased a ---903 ecu non eeprom from a 1990 gsx that worked for sure in the other car and has brand new caps.

my car would start with the old ecu, but then i would get random weird problems like boost issues and sometimes it wouldnt start.

now that i've put the new ecu in, it wont start at all...it cranks over but no start


anyone know if there is an incompatibility issue here?


thanks

 

[91 Turbo Mitsu]

Dont understand your numbers 902 903. Did you mean it had a 92 ecu and now you have a 90. If you had a 91 up ecu and put a 90 ecu in it you probably need to do the pin swap back to original nbecause the 90 and 91 up are different by two wires I think. Travis

 

[95blackGsTurbo]

902 and 903 are just numbers to ID the ECU as Cali or not. If you are sure it came from a 90 is should work eprom or not.

 

[steve]

MD145903 90 Federal AWD MT ECU.
MD145902 90 California AWD MT ECU.

The California ECU checks for and supports the EGRT input and EGR Solenoid output.

Usually the problem described would be a bad ECU but check the MPI and ignition fuses to make sure that you are getting power to the MPI relay. Put each ECU in the car in turn and make sure that the CEL comes on for about 5 seconds with the ignition on. If the old ECU does and the new doesn't then it has problems regardless what the seller said.

Steve

 

[superrandomguy]

after i solder on some new caps to my old ecu i'm going to try that. I'm a bit reluctant to plug the old one back in because the corrosion was so bad it charred the board and another little brown microchip fell off of it when i was trying to clean the corrosion.


i hope if i put new caps it should at least run well enough to start the car...