I put a 94 pcm in a 97 camaro z28 and everything has worked so far but I'm having trouble with the fuel pump. I know its good because I hooked a battery up to it directly but now im trying to figure out which wires should be hot at the relay. The only hot wire I have is orange but I'm thinking I should have another one. Please help I want to get this thing on the road!

 

Nope.

Orange- +12v (should be hot all the time)
Red- to fuel pump prime connector by pcm
Drk Grn/White- fuel pump relay control from pcm (should be hot for 2 seconds when key is turned ON and hot when engine is running)
Grey- +12v to fuel pump (hot when relay is operated)
Blk/White- ground

 

Ok thanks so much. I definately had my key turned on for longer than 2 sec so that is probably my problem but what if I still don't get power to it? Does that mean the pcm is bad and if so can I wire a switch for the pump? Thanks.

 

The relay control wire from the PCM gets voltage for about 2 seconds when the key is turned to ON. If the engine is not started (the PCM does not see ignition pulses), the PCM shuts it off. If you get nothing at either of those times, check the integrity of the wire from the relay to the PCM.

 

This may be a stupid question but what exactly do you mean by checking the integrity from the relay to pcm? Do you mean follow it all the way to the pcm and check for power there? There are several green wires going into the different connections on the pcm so does anyone know which one is for the fuel pump? Thanks.

 

Use a meter to test the wire.

PCM connector C1 (red), pin 7 > C220, cavity J > f/p relay

All this info is on my Tech Page.