Hi guys
I have a 1999 Dodge Ram, 4X4, 360, auto, 105k miles.

Truck always did great until the other day. Started it, drove about 1/2 mile to a store where it died and would not start. It turns over great. My first thought was fuel pump. But, I can hear it when I turn the key (not always an indication of a good pump) and I poured gas in the throttle body and still nothing.
My next thought was crankcase sensor. Tested and was good, but figured wth, went on and changed it out.
Hauled it home the next day, went to unload it, and it started like normal. Unloaded it and it died and would not start. Perfect timing, actually
Let it sit for a while, and it started right up. Ran for a min, then died and wouldn't start again.

About all I can think of now is perhaps the IAC, but would that effect starting?
Always idled great, though, so I don't really think it's the IAC. But i'm only a shadetree mechanic, so perhaps.

I did notice recently, at highway speed, it would surge a little.

Thoughts on what to check next? Any help is appreciated.

EDIT*
Forgot to add, no check engine light on. Ran fuel pressure test. Holds steady at 45.

 

Pressure is a bit low, but, still acceptable.

Whats missing when it won't start? You dumped gas down it, and it still wouldn't fire..... that implies no spark, but, are the injectors firing????

I am really suspecting the PCM is the problem here...... Get a noid light from your local parts store. Next time it won't start, verify no spark, and test for injector pulse. My bet is, you won't have either......

You *might* have a bad cam position sensor, (in the dist, called a pick-up coil.....) but, I think even if that were bad, you would still get spark.....

 

I'll do that. My son actually has a 2000 model, same truck, maybe I'll 'borrow' his computer to see.
Started it a few ago, held it to 2k, ran fine for as long as I held it there. I let off the gas and she died.
Tried starting, acted like it would but didn't. Did that three times and it started. As long as I held the gas down some, it ran with a slight surge (like 1k rpms). I let off, it dies.
So, you don't think the IAC is the culprit?

 

I don't think so only because if you are giving it gas during start up, it should every time. Iac will let it die at idle.

 

Good chance of more than just one problem there......

 

X2

Bad coil was my first thought. I would check to to see if it is getting a firing signal from the pcm. If not it could be the the crank or cam sensor.

With a bad iac it should at least fire up then fall on it's face. You maight wan to try removing it to see how much carbon is built up in it.

 

Wasn't the computer. Just out of curiosity, I pulled the IAC out, cleaned it, stuck it back in and it's running great.
Apparently, fuel needs air to burn. Who knew.
Thanks for y'all's help.