1987 GN no fuel to rail

Peter Howe

New Member
Joined
Aug 21, 2019
no fuel pressure and have jumped it at alternator just rescued 87 GN from underground park lot 25 years sat
 
Check in this order:
Gas?
Voltage at hanger?
Pump?

Most likely the hanger and pump require replacement.
 
Time to drop the tank and see what you have. Corroded connections, bad pump, clogged sock and/or filter.
Might get you meter on the connector at the rear bumper to see if you are getting power back there.

Probably be good to have a hot wire setup and new pump and sock on hand to install, and an inline filter to replace the one on the frame in front of the dr side rear wheel. Check out those electrical connections and have a meter to make sure you are getting voltage to the pump.
 
It's most likely the pump. I just went through this on a car that sat for 20 years. The tank is most likely full of rust. Drop the tank, remove the pump hanger, and take a look inside. You will probably have to replace the tank, hanger, and pump. That's what I had to do.
 
When you turn the key to on (but not start) do you hear the pump prime?
+1 probably bad relay if not. If it doesn't prime (and you have a good battery) keep cranking and once oil psi builds to over 4ish the fuel pump will run. (Takes a surprising amount of cranking to get 4psi on a stock motor)
 
^That's not true.


25 years means that pump is stuck and can't turn from scammer gas. I'd go ahead get your mind set on a new pump, hotwire, tank and derusting the hangar.

Here's mine after 4 years....

https://www.turbobuicks.com/forums/buick-v6-turbo-tech/88129-day-life-earl-4.html#post803566
Yes, the pump is almost certainly the culprit, but if, once all the big ticket items, tank, pump, etc, are taken care of and there's still no prime, don't forget the relay.
The fuel pump relay is a sore spot for me as it was bust when I bought my car. I had looked at the car a few times before buying, and it always started up fine. Even after I got it, I drove it 2-3 times a day because I loved the car and all was well. Then there came a spell where it sat for a few days and the thing took forever to start. Did all the usual suspects as people above point out, no joy. The fuel pump relay "bypass" feature of the oil sender is kinda neat once you understand it, but can throw you off if you've never worked with these cars before.
 
Most (I didn't) disconnect the oil pressure wiring, so cranking it may not work. Typically, it's left hanging and not secured, so it burns against the header, shorts out, blowing the pump fuse. So voltage test at hanger is a start.

Fuel filter? Possible, but 0.000 psi fuel pressure (my definition of no pressure on a fuel gage) is most likely not a filter. Besides, once the pump is working, I would recommend getting the injectors cleaned.
 
Still thinking pump, but regardless, it should be inspected at a bare minimum.
 
Time to drop the tank and see what you have. Corroded connections, bad pump, clogged sock and/or filter.
Might get you meter on the connector at the rear bumper to see if you are getting power back there.

Probably be good to have a hot wire setup and new pump and sock on hand to install, and an inline filter to replace the one on the frame in front of the dr side rear wheel. Check out those electrical connections and have a meter to make sure you are getting voltage to the pump.
Any good GN parts stores
 
Probably the pump.
Even if it's not I'd replace it anyway.
Inspect the tank too.
 
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