Found the fuel pump relay. It clicks whenever I turn the key on and off (I could hear it and feel it). I'm not sure if that means it's good or not. If not, is there a way to test it?

 

Looked more closely and saw that there is a + - marking on the fuel pump...

 

I also powered on the fuel pump and had someone monitor a fuel line into a gas can and it's pouring plenty of fuel. Double checked the spark, and the spark plugs are each sparking a good, blue spark.

 

I had someone try to start it while I activated the pump and it still didn't start. About the only difference was that white exhaust came out the back.

 

More thoughts? The fuel pump's definitely not turning on by itself, so that's definitely a problem. But it should have started once it got fuel...

the fp relay is up there above that stuff, near the firewall. the round one with a green connector is the one.

 

Green connector one is for the Blower.

 

The Fuel pump relay has a BLUE connector. You shouldn't hear it click until you crank the engine.

 

2 Black/White wires with 12v coming from fuse 11 (check that fuse)

1 Blue/white wire power out to pump

1 Blue/Black wire, from ECU to ground the relay WHEN engine is turning (determined by tach pulse from coil)

 

Easiest test is simply connect the 2 green connectors under the hood. Should cycle the pump and flash the CEL toghether.

Double checked, and no, the fuel pump relay isn't clicking until I try to start it (but it is clicking).

I wasn't able to check the voltage to the relay itself since my voltmeter died on me, but I will hopefully do that soon.

 

I tried connecting the green connectors under the hood.

The CEL came on solid and stayed on, and I heard a clicking under the hood that sounded a lot like a turn signal. However, the fuel pump did not cycle on.

 

Thoughts?

Edited March 27, 201214 yr by MilesAway1980

On my 87 GL wagon the fuel pump & ignition relays are mounted to a bracket directly above the ECU. The small light blue w black stripe wire on the fuel pump relay goes to pin 47 of the ECU. Just to test the relay & pump take a 12v test light & ground the clip then touch the probe to the LB/Blk relay connector with the ignition on. You should hear the relay click & fuel pump running. I was under the dash to wire in driving lights anyway so I tested this - it works.

Grounding this wire might be the solution for the ECU problem 86gl-10trbosdn mentioned.

Hope this helps.

 

Okay, I gave this a try. Grounded a 12v test light and then connected it to the blue/black wire. The light glowed (although not nearly as bright as it did when I touched it against the two black/white wires. The relay clicked, but the fuel pump did NOT come on at all.

It could be a grounding issue with the FP. Run a separate ground from the pump to the chassis and see if it runs. I had to do this with my 89 RX a few years ago.

It could be a grounding issue with the FP. Run a separate ground from the pump to the chassis and see if it runs. I had to do this with my 89 RX a few years ago.

 

Hah!

 

Ran a cable from the negative battery cable to the negative on the fuel pump, and the fuel pump came on with the key.

 

It still won't start, but that's definitely a step in the right direction. Going to try to jump it, but thought I'd share that first.

IT RUNS!

 

It needed a good jump and was a little flooded from all my tests with the FP.

Now, to double check, is permanently wiring the ground on the fuel pump to the frame safe? Or is this a temporary thing only for diagnosing?

 

I can't thank you all enough. You've been incredibly helpful! I don't think I could have figured this out on my own.

Glad to hear you finally got it running! Persistence is key!

Did you check some of the grounding points at the back of the car to see if they were corroded or loose?

As long as you leave enough wire to service the fuel pump & the ground you add won't catch on anything. Be careful where you put your ground connection if you use a sheet metal screw to secure the ground to chassis.

IT RUNS!

 

It needed a good jump and was a little flooded from all my tests with the FP.

Now, to double check, is permanently wiring the ground on the fuel pump to the frame safe? Or is this a temporary thing only for diagnosing?

 

I can't thank you all enough. You've been incredibly helpful! I don't think I could have figured this out on my own.

 

Mine has been wired like that for about 4yrs now, no issues.

And I'm running a Walbro pump now.

Okay, cool. I'll put a new ground on the fuel pump and finish it up tonight then.

 

I know the fuel pumps are usually wired to shut off under certain conditions like a roll-over, etc. and didn't know if the ground played into that. I wouldn't want to be going around a safety feature.

 

Thanks for the post up of the grounds on the car. I had no idea where to even start looking for those. The wires from the fuel pump just go into a hole about 5 inches away and then "disappear".