octane adjust plug

[wfcrawford]

i have a 96 mark8 motor that i am installing in a factory five racing coupe and need to know what wires i can cut out of the eng. harness
i have not herd of a octane adjust plug [pin#30],differential pressure feedback[pin#65],
can i shorten up the shielded cam and crank sensor wires
i would like to remove as much wire as i can from the pcm
thanks
wilbur

 

[wfcrawford]

now i know someone can tell me if i need the octane adjust plug or how it works
thanks
wilbur

 

[mikepietras04]

You really shouldnt remove any wires that go from the PCM to the engine. These engines depend on multiple sensor readings to perform properly. For instance, removing the wires for the octane adjust plug will create an open circuit causing timing retard (approx 3 degrees). This is to compensate for knock when low octane fuel is used.
My advice would be to leave EVERYTHING alone on the harness. MAF, IAT, ECT, O2, knock sensors, position sensors, EGR pressure modulator, ect..... they are all very inportant to helping this engine run properly.
After you have the engine installed, keep the OBDII conector intact, run a diagnostic scan on the engine, and be sure everthinbg is functioning as it should. A missing/intermittent sensor can cause the failure of an entire circuit, causing the engine to run on predetermined fuel maps to prevent damage.... this can severly render performance.

 

[wfcrawford]

octane adjust

thanks mike
the octane plug was i did not know anything about. i did not recive all the wire harness with my motor. i will go get the plug and obd2 conector
what about the rear 02 sensors. with my header setup there is no way
thanks
wilbur