I posted a while back about my Dodge 2500 5.9l 4x4 not starting for any reason. I took it to the mechanic, he said it was the brain, so he put a new brain in it. Well, that didn't fix anything. The truck will only start at totally random times. Example - started a 6am today, 12:30pm today, but won't start now (somewhere around 7-8pmish). I've checked fuses, relays, everything. I think it may be the ignition switch. Regardless if it starts or not, it always gets power, and always turns over. Any help at all would be greatly appreciated.

And yes, the mechanic and others I have talked to asked me if my truck was possessed, as this baffles them as well.

 

when its not starting are you checking for spaek or fuel ??

 

Yep, it is getting spark and fuel.

 

Ok, it is 3am (eastern time) and the truck started perfectly fine. Perhaps it has something to do with the heat? Right now, it is 52 degrees out. This afternoon, it was around 75.

If this makes sense to anybody, please let me know.

 

My girls stratus was doing that a couple months ago. Turned out it was the fuel pump relay, and distributer was part of the problem. I would throw a new relay in there and see what happens

 

Lots of possibilities, but first I'd be damn sure that strong spark (at least 20 Kv's at the plugs) are present and that fuel pressure reaches at least 30 PSI when it's acting up (30 is below spec, but it will start). If those check out, makes sure the injectors are pulsing.

I'm assuming that it didn't act up for your mechanic, and he just gave an educated guess at the PCM, because there's no reason that a competent technician wouldn't be able to accurately diagnose a no-start on a domestic pick-up truck if the condition exists while he has the vehicle. I'd get it back to him and let him keep it until it exhibits the failure. He should be able to at least determine what isn't working in short order, and then start in on the why's.

 

Fuel spec is abt 50 psi. If you have proper fuel pressure, spark and an injector pulse it should run.

Here is a tip for the future. If your mechanic doesn't know the proper terminology for the part (eg. the brain) take it somewhere else.

If he can't pronounce it he can't diagnose it... ( [sm=bangbang.gif]shakes head )

 

Brain must have been from abbie normal.