Topic: 4.3 MOTOR HELP?

[Beast2588]

I've got a 92 4.3 Vortec in an 85 Toy Pickup. So I drove my truck to get some gas, filled er up and went to start it and would fire right away then jus die. Towed it back to the house. Changed the fuel filter thinking it might be cloged, that an i dont think its ever been changed. Got that done and still jus fires and dies. So checked to see i have spark it does. Fuel pressure is at about 60 lbs. Has brand new batterys in it. But still wont stay running. So im a lil stumped at this point. Any info on what it may be would be helpful. thanks

[COToy91]

I've got a 92 4.3 Vortec in an 85 Toy Pickup. So I drove my truck to get some gas, filled er up and went to start it and would fire right away then jus die. Towed it back to the house. Changed the fuel filter thinking it might be cloged, that an i dont think its ever been changed. Got that done and still jus fires and dies. So checked to see i have spark it does. Fuel pressure is at about 60 lbs. Has brand new batterys in it. But still wont stay running. So im a lil stumped at this point. Any info on what it may be would be helpful. thanks

Didi you check to see if the injectors are firing? Check all fuses

[Beast2588 [OP]]

yea checked all the fuses they all look good. didnt even think bout the injectors. ill check that and see what happens.

[COToy91]

yea checked all the fuses they all look good. didnt even think bout the injectors. ill check that and see what happens.

I had a similar problem and it was caused by the air cleaner grounding out on the throttle body and causing a fuse to blow

[axled89]

is there a injector relay of some sort on that some where???         what about a fuel pump relay??   
    my 85 f-250   would run just fine at an idle.  but as soon as i were to go and give some throttle it acted like it was out of gas and just die.    that happened to be the fuel pump relay. and it had like 7 pounds of pressure.                  good luck bro.

[COToy91]

what wiring harness are you using for the engine?

[Beast2588 [OP]]

Not sure where the injector relay is. but i did find the fuel pump relay and replaced it with a spare i had. not sure what the wiring harness is. i didnt do the swap in this truck. but ill find out. im gonna fiddle with it tomorrow and see what happens. i appreciate the help. ill let you know what else i find and see if we can get it goin

[emsvitil]

If it starts, then dies right away,

That's a



Ballast Resistor................


 


Whoops, this isn't the slant six forum.......


 


 

[DanGT86]

vortec 4.3 motors have a lot of fuel related issues.  They are very picky when it comes to fuel pressure. I think the earlier years were worse with the central injector.  I hear a lot of people recommend taking the throttle body off and look down into the intake with a flashlight to see if there is fuel leaking out of the injector unit or the hoses under there.  A fuel leak in there can keep them from running correctly or at all.  Do some searches on s10forum.com and see what you can find.  Sorry I cant be more specific. I dont have a vortec myself so Im just going off of what I overhear from my s10 friends.

[ordan300]

I would check the mass air flow plug

[4RunnerChevy]

vortec 4.3 motors have a lot of fuel related issues.  They are very picky when it comes to fuel pressure. I think the earlier years were worse with the central injector.  I hear a lot of people recommend taking the throttle body off and look down into the intake with a flashlight to see if there is fuel leaking out of the injector unit or the hoses under there.  A fuel leak in there can keep them from running correctly or at all.  Do some searches on s10forum.com and see what you can find.  Sorry I cant be more specific. I dont have a vortec myself so Im just going off of what I overhear from my s10 friends.

The CPI had this problem but it usually just meant bad fuel economy, and smog issues.  If you have the CPI then you can pull the intake, and check for fuel leakage.  If it looks washed then replace the regulator, and get a Nut Kit.  Sometimes a poppet valve will break and a cylinder won't get fuel at all.

Any engine codes ?  The Vortec will not run without some of its sensors, so check for loose wires.

[bleakhorizon]

These engines use the "spider" injection system. . . . I worked on one that did the same thing, we replaced alot of parts as we had a couple of parts rigs. ended up being the injector unit... not saying thats your problem but it has worked for me in the past.....