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HELP. Replaced motor. Now no fuel, no crank.

1K views 7 replies 2 participants last post by  1966tbird 
#1 ·
Hi, we are new. Unfortunately we are starting out behind the 8 ball. We bought a cobalt for our son from a dealer as is. Now we know why. First its 2006 2.2l with 170k. We had a problem from the beginning where the fuse was missing for the power locks, put it in and they start dancing up and down. We removed the fuse, have random dead battery. Believe it or not this is a small problem now. The engine tossed a rod and windowed the block. We already being in a bad position ponied up for a used lower mile motor with 90k. We pulled the old one, popped in the new one (have experience with cars, mostly older) and no real issues. U til we went to turn the key on to get fuel up to the rail. We didnt hear the pump, used a allen key to push the shrader valve assuming it was just quiet. No mas even after 30 tries. So we said screw it let's turn the key and start it. No crank. Before we get the first message we didnt take wires off the starter at all, cleaned all grounds going in, and marked everything and it's where it should be. So we noticed the picture of the car with the lock is on. So googling led us to think we needed to retrain the car to accept the key. 10 minutes in run, off, wait 5 seconds, back to run, repeat, repeat, repeat. No mas. Still shows the same. The dealers around us all said yeah, without the original key(we got some hodge podge, no fob) it needs to be towed in and pay $$ to retrain it. Key opens passenger door, not drivers, so we assume the dealer was a scum bag and did who knows what. Any ideas or tricks, please let us know. My sons in tears and I'm running out of hair to pull
 
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#3 ·
Ok, well when we replaced the engine we had no fuel pump, no crank. Period. The security light in the car stays solid. Someone suggested the 30 minute relearn. Key on, try crank, leave on 10, turn off when the light goes off, wait 5 seconds and repeat. Problem is the light NEVER goes out to complete step 1. We tried to turn it off at 10 minutes, 5 off, on, and repeated to no avail and the light never goes out. We cleaned the grounds everywhere. Checked the power cables on the battery, even added a second ground for the battery. Cleaned and checked all fuses in the bcm and under the hood, cleaned weather pCks with approved cleaner. I get power on the bcm at #8,25. Under hood is getting power as well. But with the security lockout we are sitting ducks. To go one step further we got a BCM from the junk yard, installed it and same. We borrowed a friends snap on tool and it said it cannot connect to the pcm. But others say you cant connect to the pcm if anti theft is fully locked. Any real leads would be great, I've spent 20 hours cleaning, checking, and rechecking. I feel the anti theft is the issue.
 
#6 ·
Cleaned all weather packs, triple checked grounds. Now connected a higher end scanner to the obd2 port. It has power but cNt connect to the system. Checked connector with meter, the ground #4 is good and gets 12+v on #16. Is there any tests that can be done with a multi meter for data transfer and or the data ground
 
#7 ·
Update, connected a snap on solus edge. Could not read or communicate BUT. Manually set up it could communicate. Says the passwords are valid, key is valid and we can turn it on and off and see the change. DTC code shows u2105. We cant really get it to do anything. Quite the nightmare, the mechanic here is beside himself.
 
#8 · (Edited)
Did you change out the engine control unit Or body control unit?

What year car was the donor engine?

If you wish to drive. Continue on as you have.
If you want help, make it easier on those willing to help.


Do you have the original BCM and ECM in the car???? If not, get access to a TechII and rebond your system.
This would include radio, remote door locks, and other mundane items logged in the BCM such as total mileage and VIN number or you will continue to receive errors and the BCM will not pass the command to the start relay and fuel pump relay.
 
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