E99 no start, think bad PCM

Mrcrowe · Jul 2, 2013

My truck started messing up a few weeks ago, it started out a a hard start and slowly kept getting harder and harder to start. Some times it would bust right off and a few times there's nothing I can do to get it to start. I swapped the cps out from my other truck no change, checked the icp 500+ on cranking. Next I swapped the pcm and it busted right off and ran great for a few days and now I (tried pcm in my other truck and sure enough it wouldn't start so I ordered another pcm for that truck and got it going again) but now the truck doing it all over again it just slowly gets harder and harder to start a finally won't start atI all.

POWER-STRUCK · Jul 2, 2013

shorted out gp relay taking out the gp circuit in the pcm?

Mrcrowe · Jul 2, 2013

So should I discount the gp relay?

I forgot to mention that there's a relay buzzing noise in the cab when I turn the key on and wile I'm cranking on it. It sounds like the ones that are in the center of the dash under the a/c controls.

POWER-STRUCK · Jul 2, 2013

maybe 1 bad battery also

Mrcrowe · Jul 2, 2013

Both battery's are good and fairly new.

Lethalthreat7.3 · Jul 2, 2013

I had the same issue, truck would crank over but no start. I could hear a really under the dash. It was a charging issue. I put batts on an overnight trickle charge and not only did it start, it seemed to run better than it had in awhile. Checked charging and was at 13.9-good. Drove it about 50 miles to visit relatives. I was installing a new fuel pressure gauge and thought I would check the alternator again.
Started it up and caught it not charging with only 12.3v then suddenly it started charging at 13.9 again. I caught the faulty regulator just by chance.

ToMang07 · Jul 3, 2013

Sounds like a batter issue to me too. Double check the fuse box/GEM under the dash for any signs of water too.

ghohouston · Jul 3, 2013

ToMango, trailer park boys is the ****!

ToMang07 · Jul 3, 2013

ghohouston said:
ToMango, trailer park boys is the ****!

imp:

Mrcrowe · Jul 4, 2013

I can't see any signs of water/damage to the fuse box or anything else.

Mrcrowe · Jul 5, 2013

I think I found the problem the passenger side battery was not making a good connection, I finally got the truck to start and I put the volt meter on it and it only had 12v the other side had 14v. So I cleaned up all of the battery post and terminals and it started right up, so far I haven't had any problems with it. Would starting the truck on one battery cause the computer to burn up, because it still won't start on the old pcm?