used my obd2-obd1 harness and plugged in a stock p72 obd1 gsr ecu and right when it reaches 4800 rpms it kinda sputters and wont let me go past it. I can downshift for rpms to be higher than 4800 but right when i give it gas it sputters and wont go any more... could it be that i need an obd1 distributor cap too?