Shuts off and will not restart, code 42

Good evening.

The fact that it runs with added fuel to the throttle body tells me you have a fuel delivery issue.

Can you hear the fuel pump run when you turn the key to on?

Roy

Yes, it runs for twenty seconds then stops, a little tougher sound then I am use to. today fired it up ran for ten minutes shut off then fired it right back up. I am lost bad on this one. It has to be something heating up and shutting the truck off.

I would start with a fuel pressure test. you can rent a tester at a parts store to check it.

Roy

Copy that, as it was running today I disconnect fuel pump relay and it stayed running. so I am really really thinking it is the fuel pump. I have fire I have fuel, no vacuum lines off when I disconnect the coil wire it will stall and stop running, but then fire right back up when coil wire is put back on. I think the fuel pump is heating up and shutting off but there no real surefire way I checking that even with a pressure gauge.

The pressure gauge will tell if it is putting out proper pressure. it may be failing when hot.

it stays running with relay out because the oil pressure switch has a bypass circuit built into it in case the relay fails.

Roy

Correct.
My oil pressure sending unit is erratic as well but the circuit is still closed. so yes you are right on the bypass, my thought on the pressure gauge is it the fuel pump is heating up and failing with the pressure gauge on the truck when it shuts off and the pressure falls at that time again. how do I know it is a failed pump? The truck stops the fuel pump does as well I am a truck that has no problem and the pump will not come back on until the key is cycled. Correct?

correct. you need to check the pressure to see if it falls out and the truck stalls.

Roy

Okay, I see where you are going with that., let me get one and go from there. update to come. thanks

9-13 Psi if I remember correctly for that application.

correct.

Roy

Cannot hook it up, steal line in the back does not have a enough room to put in port.

Not enough adapters in the kit to put it in like in place of the filter.

But I cannot quit, lol.

Does not have a T fitting in the kit??

Roy

It does.

Friends of mine as a bigger kit I will get from him tomorrow, it may have in like fitting to put in place of the fuel filter, be way easier then trying to make this work. last thing I want to do is kink a like or mess up threads on throttle body.

Now if I can get one side of the throttle body plumbed in with tester how good of a test would it be only burning on one injector?

Still no good, only thing is I cannot and maybe check the pressure at the pump if I disconnect fuel filter, but that would be the only way this kit will work if it will?

Nope!! This kit will not do it, more to follow tomorrow.

Okay, will be on in the morning and after about 3:00 pm est.

Roy

Okay, but let me say again, the truck does not stall out at all, it shuts off as fast as it would if I turned the key off.

Yep, still need to do these checks.

Roy

At first then gauge jumped up to around ten the I sprung a leak so took all off and get everything sealed back up now zero on the gauge, but the truck runs still for about five minutes or so then shuts off. I can fire it right back up but still zero on the gauge. Fuel pump is the problem I am thinking.

Now if I take gauge off as the truck runs and bleed the line it will stall then shut off.

Something sure not right though, if I disconnect everything and let it free flow with the pump on it will sling some fuel. now it does not look like it under a lot of pressure but it does come out .

Okay, the pump can work but not supply enough pressure for the system to work.

it sounds like you need a pump.

Roy

If you look closer at the clear line the bleed off
line , I am holding the JR button down and see how fast the pressure Ian bleeding off it should really really really slow so either my
like is plugs some way or the fuel pump is putting out less then 10 PSI.

Nice video. yes I still think you have a failing pump. not enough fuel.

Roy

Nope! Bypassed the filter and has around twelve pounds steady, went inside showered and came out all along the truck was running so I’m going to change the filter Tomorrow.
And I think my problem will be fixed.

Okay, let me know. The filter has a bypass in case it gets clogged but lets see what happens.

Roy

I will do it. cannot think of anything else since it ran great for twenty minutes without a filter. maybe a combination of the two as well.

Keep me updated.

Changed fuel filter started up ran for one to two minutes, plumbed around the filter and Poured fuel in throttle body two times to get it started and as I was checking again for fire which I still have it fired up and ran for about five minutes. My thought at this point is the fuel filter is putting just enough load on an older pump and it is to the point that it cannot keep up. Thoughts? As soon as I turn the key on am I supposed to get fuel at injectors in throttle body?

That is what I was saying before. it definitely looks like a pump failing.

Roy

Not sure how it is the real mechanic world, but I had to start somewhat conservative, lol. Thanks Roy for your help. I will definitely be back in this website.

Now, so do I change the pump or the assembly?

Just the pump. Get an AC/Delco pump.

Roy

Copy all, thanks.

Check this out:

http://www.rockauto.com/en/catalog/chevrolet,1993,c2500+pickup,7.4l+v8,1033142,fuel+&+air,fuel+pump,6256

Seen that on rock auto but none were AC/Delco so I ordered just the pump on eBay for $35.00.