stumped with 4.3 fuel injection...

I have read through several of the threads on this, but am still stumped. 93 GMC Jimmy, 4x4, 4.3 vortec. Died going down the hiway. Have replaced fuel pump, fuel filter,all lines, etc., the spider assembley with fuel regulator, twice, thinking maybe the first spider was bad.
Also inspected fuel pump pulsator lines for any ruptures. Replaced hard plastic lines that mount to the spider injector. Virtually everything in entire fuel system is new.

Getting fuel up to the assembley with 55-64 psi. But still no spray out of the injectors. Do have injector pulse, or ignition spark. Can pour fuel into the intake and it will start and run until fuel is burned up, then dies. Have spent hundreds... still wont run.

Took it to GM dealer for diagnostics, they can't find whats wrong either, without manually teariing into the system as well as my wallet. Totally stumped, mechanics I talk to are stumped. Any one have any advice? Much appreciated, getting totally frustrated.

Thanks !

How are they checking for an injector pulse? Are they using a noid light (little light that you hook to the electrical connector to see if it flashes) or are they using an oscilloscope. The only way to really check to see if you are getting a qaulity injector pulse is using a scope. If that has been done and you say you are getting fuel pressure that mean you have fuel pressure and a pulse with no spray from an injector, sounds like a clogged injector unless I am missing something. or possibly an internal clogg just prior to the injector

well its gotta be a clog further front than what you replaced. it prolly would have been cheaper to go to the dealer first and had do you might of ended up spendin 300 an got exactly what you needed...ill talk to the guys at work tomaro to see if they cvame accross this b4... my dealership is the shit withthe 4.3 we got a guy that can do the intake gasket in under 30 mins...

Check for injector pulse and power at the wiring going to upper intake. If power and pulse there remove the upper intake and check the wiring at the injector unit. If pulse and power there check the injector unit for being bad.
But make sure to disable coil before cranking with upper intake off.
MT

thank you folks for your time ,by this time i have replaced 3 new spider assmbs ,i guess since it was checked with a noid led the problem must be electical i was told there is suppose to be an electronic module close to the distributor i,ll look meantime if anyone has any direction to point me. it would be very greatly appreciated

You can find electrical modules all over it but looking at them will not tell you anything.
You have to test things out.
If injector unit is not squirting fuel.
MAKE SURE IT HAS THE PROPER FUEL FRESSURE.
And then.
Read my upper post.
MT :lol2: :grinyes: