87 R20 suburban

[gtonut1]

no fuel to the TBI. Changed the low oil.pressure fuel pump cutoff switch but no difference .
Starts with starter fluid for a few seconds and oil pressure comes up.

Had just drove it for a 200 mile round trip with no issues. Parked for a week and now wont run.
Any thoughts are appreciated.

 

[Ricko1966]

There is no such thing as a low oil pressure fuel cutoff switch on a squarebody truck. Check for power to the fuel pump relay and jumper the fuel pump relay, listen for the pump to run. Post back

 

[YakkoWarner]

There is no such thing as a low oil pressure fuel cutoff switch on a squarebody truck. Check for power to the fuel pump relay and jumper the fuel pump relay, listen for the pump to run. Post back

Very accurate. The oil presssure fuel switch serves a a backup for the fuel pump relay, should keep you running even if the relay fails.

The fact that you get no fuel to the TBI even after coaxing it to run long enough to build oil pressure says your problem lives elsewhere. Because it does run when fed externally, that means your distributor is giving crank position data to the computer and firing the distributor correctly. The same signal is also used to trigger the injectors, so we can logically eliminate a distributor pickup or module problem.

I'd start at the pump itself - it could have failed after your long trip. Open your fuel fill, stick your ear against the hole and get someone to turn the key to "on" but not crank. You should hear it run (kind of sounds like a quiet hissing) for a few seconds. If you don't hear it, you now know where to start troubleshooting.

If you do hear the pump running, then its time to start looking at fuel lines (a clogged filter could do it) or the injector wiring (or maybe the injectors themselves). But no pump means no point even looking elsewhere.

 

[89Suburban]

@gtonut1 Beat the bottom of the fuel tank with your fist or a mallet a few times see if it kicks the pump in. You should also see fuel spraying out of the injectors in the throttle body while it is cranking.