lsapache

hello everyone, I just bought a 85 iroc with a 305 tpi. I bought it for 600 and thought I was getting a steal, come to find out may have bought myself a headache.

Issue is when I picked up the car, the guy said he ran it out of gas. no big deal because I heard it run before that. After messing around with it, I can get it to prime and start when I bypass the fuel pump relay at the firewall. So I taped the inside of the relay so the circuit would stay closed. When I plug in the rigged relay the pump comes on and stays on even when the car is off. Figuring the relay was bad I bought a new one and plugged it in but it doesnt work. The motor cranks and has spark but no fuel. Once I plug in the old rigged relay the pump comes on and stays on and car runs fine but they pump always stays on unless I unplug the relay.

I have looked through a lot of threads to no avail. Someone had messed up a lot of the wiring. I have tried looking for the inline fuse by the battery but my car doesn’t have one. I would appreciate any help in the matter

zed-028

http://92b4crs.tripod.com/86wiring/86wiringindex.html

not 85 but close enough. might find some wiring info in here

zed-028

i think the fuel prime is triggered by power to one pin of the ignition control module, the pump itself is triggered by the oil pressure switch so it is only active when there is oil pressure (cranking and running) if youve got a dead oil pressure switch then you arent going to get any trigger 12v to the relay to make it run - the reason it wont turn off is because its still getting power from another source, the oil pressure disappearing should kill it off by design.

lsapache

Thank you for the reply. The picture I have attached is from the fuel pump relay. The only way I can get the pump to kick on is by jumping the 2 outside wires. The orange on the right is 12v constant. I can’t get anything from the other wires except the black one which sparks because I assume that’s the ground. I will look into the the ignition control module I appreciate the advice also I believe most if not all 85 Camaros had a external type coil distributor is this correct? The one on my car has a normal hei distributor. Asking so I now if it could be stock?

zed-028

hmmm you might have to wait for someone with a TPI setup to answer that one.

in the meantime, find the wire for the oil pressure switch, attach a test light and have a mate hit the key to turn over the motor.

if you get no light, you have a dead oil pressure switch.

if you get a light, then put a test light on one of the wires on that connector you posted, crank the engine again, if you don get that same light while cranking, chances are you have a break between the oil pressure switch and the 12v trigger wire going to the relay.

ploegi

The oil pressure switch is backup power for the fuel pump, it is not a safety device of any sort. If the fuel pump relay fails, the oil pressure switch SHOULD power the fuel pump once you have cranked long enough for oil pressure to come up. If the relay is working as it should, it just doesn't matter if you have oil pressure or not, the pump will still run, so long as the ECM sees the engine turning. (ignition module.)

Need to find out why the ECM isn't triggering the relay.