84 fuel pump problems

[wicked4d]

I have an 84 svo that had a rusted out fuel tank, before replacing it the pump would try to prime, but sounded weird and the car would not run right. The tank was full of rust and crud. I replaced the tank, pump, and sender with a 86 style pump setup. Now, the pump will not prime. I have power at the fuel pump relay (yellow wire), and at the inertia switch. I have tried swapping the relay to no avail. code reader gives code 11, all ok. When the iginition is turned to run I get a jump in voltage to both fuel pumps for a fraction of a second, then no voltage.

Got any ideas what to try next?

Thanks guys.

[SVOJames]

I am no good at diagnostics, but I'll throw in my 2 cents for free:

The 86 setup is a single (in tank) pump, as opposed to the 84/85 dual pump system.

I believe there is also a resister that needs to be deleted doing a 86 fuel pump on pre 85.5 models.

[wicked4d]

I have tried grounding the pump before the resistor wire temporarily, and also tried grounding the test connector right pin to no avail.

[Erics SVO]

Possibly the ignition switch. When they get worn lotsa things can get funky.

[Alex L]

wait wait wait. before we start tearing apart the steering colum, lets go over this again:

rusted tank, pump primed, prolly sucked in a buncha junk
swaped tank, pumps, etc etc
voltage hits breifly to the pump harness in the body when key'd on, but pump does not prime.

electrical is good up to the tank harness. depressurize the fuel lines, drop the tank (should be easy since you just put it back in), pull the harness and confirm you're getting voltage at the harness to tank connector. you most likely will. move the tank to a safe distance in a well ventilated area, make sure you have fire extinguishers along your exit route, pull the pump and make sure it didnt drop a wire. take the pump and reattach it to the harness and see if it primes outside of the tank. if it doesn't, you got a bad pump. if it does, you got a flaky wire somewhere between the body and tank.

[Pat_in_L.A.]

You can check voltage to the fuel pump. If it ain't getting voltage, it ain't gonna run.

You can do the same thang with the relay under the driver seat. Once again, if it ain't getting voltage, it ain't gonna run.

You can do the same thang with the EEC relay in the pasenger footwell. Once again, if it ain't getting voltage, it ain't gonna run.

[wicked4d]

Everything's good now, replacement pump was bad, should have checked for continuity before bolting the tank back in, or dry tested it. What a pain to track down. I narrowed it down to the pump or the pump harness.

I think I can drop the tank and replace it in 10 minutes now.

Thanks guys - there is another one on the road after 10 years sitting!

[Alex L]

Thanks guys - there is another one on the road after 10 years sitting!

w00t!

burnout pics or it didnt happen!