rithsleeper

1989 6 speed. Im completing my installation of my holley commander so I dont need my stock wiring or ecm. Im looking at the wiring harness and cant identify some of the wires and I cant locate my supplemental electrical fsm. Can I remove all the wires from the stock ecm or do I need keep anything from that harness?

The holley runs injectors reads all sensors, and runs the ignition. No ac, i am keeping my stock dash, need to keep it street legal even though it's 90% track car.

About the only problem I see is removing the vats. I figure ill just put a straight wire from the ignition to bypass the entire security since I dont use the stock ecm and holly runs fuel pump.

Thanks for any help you can give me.

Bad Karma

What year is the car? Once they hit the digital/analog dash (I think in '90) there's a body computer that gets unhappy if its not talking to the ecu.

Black89Z51

I've gotten rid of my FI, but from what I can remember gutting my car, I don't think the ECU controls anything else. Maybe some of the gauges, but that's all I can think. I will check this evening when I get home.

rithsleeper

1989

Race Prepared

Get rid of some wires? What "wires" are you wanting to eliminate. Perhaps someone could provide assistance with photos and a better description of what you are trying to accomplish. ABS, FX3, O2 sensor, cooling fan relay, knock sensor, ......

rithsleeper

Its not that I need to specifically identify wires unless they are needed to make the car continue to function. I want it all gone. It might be easier to list what I need to stay intact on the car from factory.

I still need lights inside and out, seat controls, dashboard needs to display oil pressure, coolant temp, oil temp, volts, speed, and tach. I am going to run a wire from a starter button to eliminate need for vats and a key, fan on a switch, ac I am wiring as an on off switch (on high or completely off blowing defrost/front). Still need all turn signals and windshield washers.

I am done with fx3, no abs, no engine management because new holley takes all that over, no vats, no ac controls, no stereo/speakers, no warning light display, it is all completely unecessary to me now.

Im ready to just start cutting and figure out rewiring from nothing might be easier than trying to remove intact. How much is a used ecm with wiring harness worth to begin with. Prob not as much hassle and time ive put in already....

BrianCunningham

On an early C4 the gauges should still work, just need to hook them up to the sensors

exracer28

You will have to look at the schematic and determine what interfaces with the ECU. Circuit analysis may be boring but it will determine what can be deleted without surprises. Keeping the stock gauges will require more interface than you would expect. Power seat is minor compared to gauges. Look twice before you cut.

Zip Corvettes

No tech is going to tell you which wires to remove and which ones to keep. First off they may be tech but it does not mean they have everyone of the wires memorized with there color and what they go to.
I have done several cars with DFI, a 89 would be easy. You just need to label each wire that goes to the engine, TPS fuel injectors distributor etc. All engine controls, but you do not want to eleminate gauge sensors. You can then wire your Holley commander in a be done. The only think you are going to lose in this is the fuel mileage avg and instant.