bschulze

It will start and run a bit if you pour gas in a throttle body.
Tank has gas. Fuel pump runs, pumps up and shuts off.
But, it won't start.



Is there another filter in the throttle bodies to check??
It ran fine and then it didn't any more.



Would appreciate some ideas for things to check.


Thank you,
Bob

84 4+3

Are you getting pulses from the injectors? Fuel at the throttlebodies?

bschulze

I'm thinking that there is gas to the throttle bodies as the pump is shutting off. Don't the throttle bodies control the pump off/on?


If I put a finger on the injector body above the throttle plate, can I feel the injector pulse?


There is no gas spray there.


Thanks for the reply.
Bob

84 4+3

The fuel pump cycles on a time delay at key on, if you're getting no spray it either isn't getting a signal to turn on the pump or the injectors aren't pulsing fuel into the throttle bores. If you hold onto the injector pod you should feel it click while cranking it you're careful. If you have a test light you can ground it to the injector lead and it'll blink while pulsing. Let me dig up my service manual and snap a few pics for you from the trouble shooting section.

84 4+3

These should help some.

bschulze

Thanks for reply. If I can feel the injector pulse but no spray, then it could mean no gas to the injector? You mentioned: key on and a time delay and the pump shuts off.



The fuel line filter has never been changed in 50k plus miles. And it has been run on ethanol. Could it be as simple as a plugged fuel filter??

I thought since the pump shuts off it meant pressure to the throttle bodies. The key on time interval shut off is new to me. (I'm trying to help a neighbor)

84 4+3

Nope that's how it works. If you follow through that flow chart it shows the no fuel diagnosis. Fuel filter wouldn't be bad. I'd check to see if you have fuel pressure while cranking too.

bschulze

OK, I have a fuel pressure gauge. Is there a tap under the air cleaner to attach it to?

I recall a spud near the pressure regulator on my 95 Caprice. Is there a similar pressure tap under the air clnr housing?
Thank you,

Bob

84 4+3

There is no tap on the 84s. You can T into where the filter is with hose and a T (system runs around 9 psi so...) or build an adapter from parts. You could also ground one of the pins on the obd port and make it force run. If it kicks off like that you can go through troubleshooting individual systems.

red vet man

Have you check the Fuse for the injectors ?