Died and won't start

[tcheat]

Newbie here. I recently bought a 1991 4x4 (4.0L) Comanche with AT. The truck has 126k on it and was from Oklahoma, so it doesn't appear to have any rust. I've been working on it slowly trying to get it road worthy.

 

I don't drive it regularly. Yesterday, I had to jump it due to a dead battery. The truck seemed to be running normally, and then it just died. I tried to restart it, but it would "catch" then it seemed as if it was choked off and would die.

 

Up until this point, it ran pretty well. It has new plugs and wires, as well as O2 sensor. Haven't had time to start with diagnostics yet, but would appreciate any advice that you might have.

 

Thanks!

[comanche12]

try check alternator output and battery load test.

 

can be both or either r bad

[tcheat]

Thanks, 12. To clarify, I've got plenty of juice to crank it over. But it isn't starting. It seems like it wants to, but then seems like the engine is being choked off and dies.

[comanche12]

your welcome

hmm? well IIROC, did you check if it got spark? if yes then check fuel system. If no, check cps?

 

edit: also did you checked vacuum hoses too?

[maddzz1]

If its cranking but won't turn over, my guess is the CPS. Try unplugging the CPS connector and then plug it back in; then see if it starts. Sometimes this will work

[tcheat]

I checked and didn't see any vacuum hoses that looked unhooked.

 

Tried unplugging the CPS and plugging it back in. I still didn't get it to start. I'll take it off this weekend and clean or replace the CPS and see how that goes.

 

I appreciate the advice.

[tcheat]

I checked and didn't see any vacuum hoses that looked unhooked.

 

Tried unplugging the CPS and plugging it back in. I still didn't get it to start. I'll take it off this weekend and clean or replace the CPS and see how that goes.

 

I appreciate the advice.

 

Replaced CPS, no go. Had a cap and rotor, so I replaced those along with the coil (it has new plugs and wires already). Still no help.

 

Tried the "loaner" fuel pressure gauge set from Auto Zone. I'm only seeing 10 psi at the fuel rail. I replaced the fuel filter. It had a lot of dirt that drained out with the gas it was holding, but I'm still having the same issue. I've checked for fuses and didn't see any blown. I'm supposing that a new fuel pump is in order now?

[tcheat]

Just to close the loop on this one (maybe it will help someone in the future), it was my fuel pump. I used the loaner pressure gauge from a local Auto Zone. It cost $160 to borrow, but they refund all of that when you bring the kit back. My truck was showing 0-10 psi at the fuel rail.

 

I dropped the tank. When I pulled out the fuel pump/sending unit assembly, I noticed that the fuel hose was disconnected from the pump. The hose looked as if it had been chewed up (from ethanol in the fuels we use now?). I replaced the hose, reinstalled the tank and the truck started immediately.

 

The old pump began whining loudly, however, after driving it for 30 minutes or so. I bought a new pump from Napa, installed it and it runs like a champ.

 

I appreciate everyone's help.

[comanche12]

:cheers:

 

your total welcome and did you replace the fuel filter too? sorry if i miss that.