No Fuel Pressure

[MSheff]

I was driving home from work a few days ago in my '86, all was well with the world. Suddenly started to cut out and then died. I tried starting and nothing. Towed it home. I can hear the fuel pump run when I turn on the key. I pushed the valve stem on the fuel line (car was cold, I had turned the key a few times to build pressure), no fuel pressure. I didn't put the gauge on it, but it appears to be zero. My gas gauge says 1/2 tank. I jostled the car and can hear fuel sloshing around, gas gauge isn't totally lying. I am hoping to get a chance to take a look at it this weekend, so just thinking through it right now.


Possibilities...


Clogged fuel filter
Clogged fuel sock at fuel pump
Fuel pump that I can hear running, but isn't pumping?
Looking for other ideas...


So I will start with the easy stuff first, new fuel filter which it is probably time anyway. After that, it is dropping the tank. Just looking for any ideas it could be before I go to the trouble of dropping the tank...

[Laredo]

Max, has the in-tank fuel hose ever been replaced? This is the "s" shaped hose about 3" that runs from the actual pump to the fuel pump housing connector. If (when) the hose gets old and rotten, it can burst. Then all the fuel pumped out of the pump just dumps out right back into the tank, and...no fuel pressure.

9569

[MSheff]

I have never replaced it, so that is a definite possibility. Glad you brought it up, because I could have pulled the tank, not looked at the hose closely and been stumped. Thanks for the tip!

[Laredo]

I had this happen to a Turbo Coupe several years ago. Circumstances / symptoms exactly as you described.

[rodster]

Man, another Preventive Item to add to my list. :( Good info.

[MSheff]

We finally got some decent weather that matched my ability to get out and work on the car. I dropped the tank and removed the fuel pump. I don't see anything obvious where it might be leaking from the hose. It actually looked pretty good. There were a couple of scratches on the hose, but I think that may just be where I was trying to the fuel pump out of the hole. The pump is a Walbro. I have ordered a replacement and will get it back in as soon as I get a chance. I suppose the pump could be pumping, but leaking internally?

[MSheff]

Well.... It turns out it wasn't the fuel pump at all. Put the new pump in. Car would start and run for a couple seconds. Checked fuel pressure, it was fine. Just standing there looking under hood and noticed boost hose looked odd. It had popped off, likely the problem the whole time. Not sure how I measured 0 fuel pressure. I am taking the high road here, thinking that the filler neck gasket was so bad that it was about to leak soon and I now have the spare fuel pump I was needing.

[Raven855]

It’s a good item to get done. Fuel pumps, timing belts, ignition switches and stuck caliper pistons seem to cause the most problems.