Fuel pump working 40 psi on rail no start

[Tiha]

Hey, everyone - read through here and I have a similar issue...

Crank, fire, but no fuel to start up. No fuel pump sound. Replaced fuel pump relay under hood just hoping (it is 34 years old), because honestly it's a classic "ran when parked 3 weeks ago" scenario and I just knew it was that...

Aside from possible fuse(s) -which as I gather is #9 in the box (any others?)- anything else to check before I drop the tank?

Again, from all indicators it's the original fuel pump, as these were the original relays, and last fall I found a factory spark-a-lator in cyl 7...

Oh, I'm about to check the MAP trick I read above my post...

UPDATE: MAP trick doesn't change results - sinking feeling my fuel pump died. Any other tips? Also, no CEL lights, etc. No fuel smell.

I will update if/when she's up and running again View attachment 32246

The fuel pump relay.

Do you feel or hear it click on when you turn the key on?
Do you have someone to help you test it? It only stays on for a few seconds after you turn the key on.

After that you can pull the relay and use a paper clip to jumper from Yellow to pink/black and that should turn the pump on. If not, then take a test light and check for power at the tank.
If you have power at the tank, then you need a pump.

If you do not have power at the tank then move to the interia, or safety switch.

One other thing to check is the tank ground. Does the fuel gauge work? Or is it pegged?

 

[91BroncoPickup]

The fuel pump relay.

Do you feel or hear it click on when you turn the key on?
Do you have someone to help you test it? It only stays on for a few seconds after you turn the key on.

After that you can pull the relay and use a paper clip to jumper from Yellow to pink/black and that should turn the pump on. If not, then take a test light and check for power at the tank.
If you have power at the tank, then you need a pump.

If you do not have power at the tank then move to the interia, or safety switch.

One other thing to check is the tank ground. Does the fuel gauge work? Or is it pegged?



View attachment 32247

Fuel gauge has been squirrelly the entire time I've owned it. Kinda bobs around. It does show full properly, but kinda bounces under a half tank.

Nope, don't hear the fuel pump cycle or any click upon key to on position.

The relay was replaced, but made no change.

Fuses are all good as well... I will look up those other things you mentioned.

Thanks for the reply!

 

[91BroncoPickup]

Had a mechanic install the new fuel pump inside the tank for me about 4 months ago... They cleaned the tank, replaced with good fuel as well, etc. Ran great, aside from poor fuel economy.

Fast forward to 3 weeks ago when it completely died and I determined it was bad gas... Changed fuel filter, old fuel was brown milky looking crud. Replaced fuel pressure regulator, upgraded to multiport fuel injectors also. Did new plugs and wires as well, and an oil change. Then, I decided to tear into the entire thing and refresh all gaskets on top end, valve cover, plenum, EGR and throttle body gaskets. Cleaned up everything and painted the valve covers and plenum... Got everything put back together all spiffy...

Plugged everything in and double checked all vacuum lines etc...

And...


Crank no start... Seems like no spark. Has that flooded feeling, and I get fuel pressure (I think, but might not be - I do hear the fuel pump buzzing, but no clicks in the engine bay).

Harness to ignition coil shows correct voltage etc with Key on, engine off. And vacate the reading with Key off... No voltage from the point the wire from the coil to cap goes... So it's hopefully just that annual weak link.

So, yeah it won't actually start... I have a lifetime replacement on the ignition coil, so I'm about to swap that out (3rd time) and see if it starts... (Is an MSD or similar a good investment?)

Never a dull moment.

 

[L\Bronco]

Hey 91, a quick check is to put a test light between ground and the green wire at the coil and crank the engine.
The light should flash while cranking.
Is there a chance your new paint job is keeping the dist housing from being grounded? It uses a case ground for the PIP sensor. A quick check there is power your test light (hook to B+) and probe the dist housing with the key off, it should light.
Just a thought.
Cheers

 

[91BroncoPickup]

Hey 91, a quick check is to put a test light between ground and the green wire at the coil and crank the engine.
The light should flash while cranking.
Is there a chance your new paint job is keeping the dist housing from being grounded? It uses a case ground for the PIP sensor. A quick check there is power your test light (hook to B+) and probe the dist housing with the key off, it should light.
Just a thought.
Cheers

I just used the spark plug tester and it's getting spark (I also just put the new ignition coil in, so I was thinking it would get spark)...

That said, it still isn't firing off. Now I think it's the fuel pump again. It seems like there just no fuel.

I don't smell fuel in the engine bay at all either.

I'm puzzled. I don't want to drop the tank (again) but if I have to...

 

[91BroncoPickup]

Hey 91, a quick check is to put a test light between ground and the green wire at the coil and crank the engine.
The light should flash while cranking.
Is there a chance your new paint job is keeping the dist housing from being grounded? It uses a case ground for the PIP sensor. A quick check there is power your test light (hook to B+) and probe the dist housing with the key off, it should light.
Just a thought.
Cheers

Well... I might have found something here.

Brown relay has a hole burned in it...

I'd assume that is a problem!

 

[91BroncoPickup]

Figures. It's the EEC relay. Controls all EFI.

Well... I wonder if I can swap in another temporarily?

 

[L\Bronco]

Figures. It's the EEC relay. Controls all EFI.

Well... I wonder if I can swap in another temporarily?

Good find!
Brown is EEC power, green is fuel pump.
If you find one that will plug in, it should work, the color denotes the current capacity, so Id try and source the right one. But no harm in trying one to see it it will fire
Cheers