88 Fires right up then dies a few minutes later
 

1988 Bronco 302/C6/4X4
Just pulled it out of storage yesterday, been in for less than a year, and after changing the oil and putting in some dry gas and about 5 gallons of fresh gas, I cranked it over and it fired up immediately. Ran at high idle for a few minutes, then as soon as the rpms dropped down it died. Started it back up same thing happened but in a shorter time. Every time I start it same problem. What could be going on with my truck?

Run KOEO and/or KOER tests. Fault Codes should help in indicating the problem. Any time the engine stalls without being shut down with the key, the computer flashes any faults to memory.

KOER came up with code 42 i think that means running rich? I had to pull the battery to recharge as it had gone dead, and when I ran the koer test the truck stayed running

Sounds like an alternator problem, the battery is running out of juice and the alternator is not providing enough juice to keep the engine running.

Bucket full of possibilities for what you described. Hopefully you'll be able to eliminate some of your thoughts and actually narrow it down to something that'll get it going.

The first thing that entered my mind was a bad vacuum leak. If you can keep it going by choking air from it, a leak may be possible.

Next I thought of fuel supply issues (pump, cracked lines, gummed up filter and the such).

Then there's always the electrical issues to eliminate.

Gotta have three things to "go": air, fuel and fire. Start with one of 'em and start troubleshootin' till you find the problem. A decent shop manual would help immensely. Most lay out a pretty good trail to follow that'll aid the process.


If you've determined what the problem was, post back with the results. I'm interested in finding out what the issue actually was. Kinda like a cliffhanger at the end of the movie!

OK, so this has happened to me in the past. Starts and idles a bit rough, then dies. Or starts and runs but surges a bit, then dies.

I was chasing things and got to thinking about computers (ECM) and small signals... So I made a new ground wire out of some #6 stranded and ran it from the bat (-) to the firewall (pass side) using a hood hinge bolt. That seemed to help. So I did it again from the throttle plate hold down bolt to the firewall on the other hood hinge bolt - bingo. Starts, high idles, runs smoother, runs well.

Seems that the old block ground (a PIA to get to...) was corroded a bit and the ECM was not able to get a good reference ZERO (ground) for all the sensors. Once everything was tied up with new grounds (cleaned surfaces, soldered connectors, greased threads), the whole system runs much better.

Then I found out about the alternator charging issue and the need for a good ground for that, so I made one that goes from Bat (-) to the alternator body (bracket bolt) and the volt meter settled down and the system is again even happier.

Can't have too many good ground points on ECM controlled engines. And the little braised ground strap that goes from the fire wall to the manifold is getting long in the tooth. Mine was badly corroded on the motor end. So I acid dipped it, tinned it and soldered both lugs to the braid. But the new wire on the other grounds does more I'm sure...

I've now done this to 3 1980's Ford trucks and they all run much better :)