so i dropped a d15b vtec into my 91 civic hatch dx. it has a p28 ecu and a conversion harness from rywire. the car starts and runs fine at idle but as soon as i hit the gas it dies, i can floor it and it will continue to run but it runs like **** and the rpms go down to like 400. any suggestions?

 

Any codes?

Before we used to do our harnesses we currently offer, we used some other supplier, and I had a similar issue but it was an OBD2 to OBD1 conversion. If floors, it would rev shorta slow, and that was the only way to get it up and running, and test drive, it bucked and ran terrible.
We have some crossed wires in the conversion, and it took hours. Unfortunetly, I don't remember which wires were crossed, when we found, we corrrected and it ran fine. However, whatever was crossed was getting a single so that it wouldn't throw a code, but ran poor.

Good luck

 

really? cuz the harness that i got had a switch you could through to make ur CEL blink but everytime i try to use it it gives different codes. like now it might be a 5 but in 10 min it could be 27 ya know so i dont know im not real good with the whole electrical part of the car im more of a drivetrain block type mech so any help is much appreciated