Bad PCM/ECU?

Turned off and let sit went to start and nothing. I got it to start maybe four times ran badly. Today Saturday put old PCM back in fired right up and ran like a champ! But then shut off five minutes later and got a code po601. Let the truck sit for two minutes then fired right up and I let it sit and idle for about twenty five minutes turned off came in the house for the night. Very confusing, haha! Okay, thanks again.

Okay, yeah, that is what I was thinking. I will get a hold of the seller and send it back for another or re-flash. I will keep you updated. Thanks again Ken.

Okay Ken, here is the latest update on my truck. I been through three PCM's first two did the relearn and motor would miss got the third PCM did the relearn and motor fired up ran good no miss but engine light was on and dash said oil change and reduced power. After fifteen minutes motor started missing. We checked for codes and got po107, po123, and po315. We tried to delete the codes and would not go away. Seller told me to check for bad sensors and I cannot do the idle relearn until all codes are off. I figured I would try new sensors anyway and hope for the best. So I went ahead and got a new map and crank shaft position sensor put them in today started motor ran fine but engine light and codes still there after fifteen minutes motor started missing. Tried to disconnect battery for twenty minutes put battery cables back on codes still there. Tried to delete and no still there. I emailed the seller I should say has been very helpful and willing to help. I have not heard back from him. More then likely probably wants me send this PCM back and he will send me another. But I have a feeling I am going to go through the same thing as I went through the first three times. I am at a loss here. I do not have the money to send to a shop trying to do this on my own with my good friend who is a mechanic. We are both at a loss. Okay, thanks guys.

Hey thanks Ken for the information, I will take a look. I have to ask you can I take my original PCM in to a dealer and have them test it for codes like po601? I know code means faulty PCM, but can they rebuild it and flash it and how much? I am going on the fourth PCM from the seller and only one worked motor start, but fifteen minutes started missing. He is sending me out another PCM I have a feeling I will go through the same things like before. Also, do all the codes need to be gone before I do the crank cam relearn? Or the two codes that mean PCM needs to be relearned to crank okay? Also, can a good shop scanner do the crank and idle relearn? Sorry for all the questions but I know I will get the right answers from you. I tried asking the seller but he is not clear with me. Thanks ken.

Hey Ken here is the latest update on my truck. I got the fourth PCM did the relearn and motor ran great for about ten to fifteen minutes then miss. So I called are local shop and the mechanic did the crank and cam correlation he charged $50.00 for a five minute job but that is okay. Mechanic called me about an hour later said my truck was ready. I picked it up drove it about forty miles went to a friends house turned motor off and visited for about fifteen minutes went to start the truck and fired right up then shut off. I started back up and engine light was on so I drove home and checked codes I got a po0014. I cleared the code and never came back. Since then I have driven my truck about four hundred miles and it runs great! Thanks ken for all the great advice!

I had the exact same problem with my 2005 Chevy Colorado Z71. It would unexpectedly give me the Traction Fault and then "reduced power" announcement and then just shut off. It would restart most time a few minutes later, sometimes longer though. I was getting the P0601 OBDII code, internal memory problem with PCM/ECU. I ordered a PCM from eBay and replaced it. I went through the relearn process and it started on the third time and runs good. I am however getting a new code which is P0315 /Crankshaft Position not learned. I read where GM designed that to happen, so you have to get that one done with a Tech2 Scan tool. It does not affect how it runs but I heard it won't run as efficient, so I made an appointment to have it done at a local Chevrolet dealership. They said it will cost $135.00 plus tax. I only paid about $145.00 for the PCM, so it is a bummer I have to almost spend as much for that one code. Overall though, still much cheaper than it would have been if I had it all done at a dealership. By the way, I had to change the PCM about seven years ago as well, but I think it was for a different reason. It looks like it lasts about six or seven years each go!

I ended up finding a local garage with a tech 2 scanner. They did it while I waited and only charged $70.00. That is about half the cost of the dealership.