I have a built gsr (srp pistons, crower cams, etc etc...) in a 1996 acura integra gsr shell

i bought a obd2a-obd1 conversion harness and the car runs like crap with the obd1 ecu. when the obd1 ecu is in, the idle goes crazy like i have a vaccum leak but its just fine with the obd2 ecu.

i feel a big difference in the way the car drives with the i tried a obd1 jdm p72 ecu and a obd1 usdm p72 ecu and both are the same. no CEL's...

the obd2 ecu acts up as well, when i turn it on cold the idle automatically drops to like 500 rpms, (doesnt idle high at cold start up)