Fuel System struggles.... 87 TBI

[Ruuddawg]

Hi All- New to site- So I am fortunate enough to have an 87 Jimmy with the 5.7 TBI. I do not drive him enough so a couple weeks ago I got motivated. had to jump it and it fired up and ran for about 3 minutes than died. than would not restart even jumped.
So guessing fuel had gone bad I:

• added a couple new gallons, nothing,
• got new battery- turns over but nothing.
• changed fuel filter, nothing
• changed spark plugs, nothing
• used spray starter- fires up and dies after a second or 2
• got new fuel pump relay: nothing (still don't hear pump prime...)

Any suggestions, however I'm worried I gotta drop tank and get new sending unit pump assembly... I'd love to hear anyother tips to check before having to drop it- what a pain.
Thanks
Ruuddawg

 

[ktmoutfront]

There is a wire with a plug on it at the fuel pump relay. If you put 12 volt power to it, the pump should run. If not, it is pump replacement time. You do not have to change everything in the tank. The pump can be changed in the pickup unit. Pulling the tank or cutting an access panel in the floor are the only way to get to it.

I changed mine on the trail Sunday in Moab. Access panel saved the day.

 

[wyo_tom]

Like this...


Then have your sheet metal guy bend a new panel out 1/2 hard stainless and dzus it in

 

[dyeager535]

Pump not priming is pretty indicative it's the pump or pump wiring, assuming one of the two relays was good.

However...as suggested, see what the pump does with the relay "bypassed" before doing anything else.