robert1973

Ok so I am new here on this site and I have not found what I am looking fo so I will start a new thread.
My issue is my fuel pump quit working with the ignition switch I can make it run by jumping it at the relay and at the ballast resistor. So I have ran into a road block and can't figure out why it will not come on with the Ignition switch. Any ideas will be appreciqted and yes I have replace the fusiable link the ballast resistor and the relay along with the switch but still get nothing.

DFlintstone

That's a good one...I'll sleep on it. The ign switch? You do know it only runs a couple secs after you turn the ign on, then again after it starts. AND, you need to jump both the resistor and the relay?

Welcome Btw! Don.

robert1973

Ya I have jumped them both at the same time and individually and the fuel pump comes on, but like I said not with the ignition and as far as that goes none of the idiot lights on the dash come on with the key either. So wondering if it is the switch or the ECM that could be the issue.

Miamistation

I am having the same problem with my 92, This happens to me every winter, Fuel pump will not engage with the key, but when it is warm out it does fine, Im lost to, I will follow your post. I have replaced everything still have the problem. Have you tried turning the key to the on position and letting it sit for a few min? Best of luck!

freegdr

Check all fuses for power in and out with key on yet ?

cruiser54

Swap these relays around and see what happens.

cruiser54

Keep in mind that the OP's 88 is a completely different system than your 92 and shares very little in common.

robert1973

I have replaced all of those relays and yes I have left the key on for quite a while, while I have been running my test. As far as the fuses go yes I have checked all the fuses for power into the box and most do not have power into the fuse box hence the thinking that it may be the switch or the ECM.

cruiser54

There's no fuse to the fuel pump circuit.
You should have power at terminal 86 of the fuel pump relay with the key ON.

DFlintstone

I was asking if you really need to jump them both. (seems odd). I guess you are sure just jumping the resistor won't do it?

Likewise I assume you changed the correct relay, the second one back. Maybe try yet another on the outside chance you got a bad one. Easy enough to just swap in say the 4th, (ac), as Cruiser suggests.

I don't think there is a fuse, but a fusible link. There are about 5 of them coming off a big stud on the starter relay. See if any look burnt...

I believe the ECU grounds terminal 85 of the relay to run the pump.

DFlintstone

MMMM, those may well have a fuse......

Sounds like the ignition switch, or it's plug.

cruiser54

ECM could care less about your dash lights. The ignition switch on the other hand..........

freegdr

Did you have key in run position when testing ? On back of fuse box theres 4 or 5 main buss bars if all fuses on a single bar are dead main suspect would be Ignition switch.

DFlintstone

How about he check for 12v on the large yellow wire (3rd back), on the ICU, ign. on. Maybe it only runs because it's back feeding when he jumps it.

Off the switch, is yellow ign, and orange accessory? I can't seem to find anything clear. That would be the "power at terminal 86" correct?

robert1973

It was the ignition switch the whole damn time, but all is good now at least I have a fresh fuel system out of this.