Computer program after engine swap
Thread Starter
Instructor
Joined: Jan 2008
Posts: 179
Likes: 26
From: Fort Walton beach Florida
Computer program after engine swap
I have installed an Lt4 motor in place of the LT1 after the LT1 lost a valve and destroyed the block. Car is back together but I have a anti theft light on the dash and car will not start or even try and Fire. All the dash, doors, lights, windows and key fobs work on the car. Can not put the car in neutral.
Does any one have any experience with removing and replacing the motor in a C7. I did switch from the LT1 to the LT4 and used the wire harness from the Z06. I have the z06 ecm and the original ecm and have tried both with the same result. I have found no clear answer on how to clear the anti- theft system.
Does any one have any experience with removing and replacing the motor in a C7. I did switch from the LT1 to the LT4 and used the wire harness from the Z06. I have the z06 ecm and the original ecm and have tried both with the same result. I have found no clear answer on how to clear the anti- theft system.
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,009
From: Texas
What year car and what year LT4 engine?
Pretty sure you need to use your PCM so the VIN matches the BCM. With your PCM you'll need to modify the LT1 wiring harness or check and re-pin as necessary the LT4 harness. Once it's running you have to account for the boost. If you use the LT1 harness you'll need to split the IAT from the MAF and possibly more.
You can copy the LT4 tables over to the LT1 tune.
For no-crank, double check the little black wire that goes to the negative battery terminal and that the positive terminal is tight. Test the various fuses on top of the battery. Lastly swap the fob battery and/or insert the fob into the slot on the steering column.
I'd strongly recommend you visit the HP Tuners forum. The Gen V section may have some better specifics and there are a lot of really sharp folks over there. Some do remote tuning and may be able to help. Jason is on this forum...@Internets_Ninja
Pretty sure you need to use your PCM so the VIN matches the BCM. With your PCM you'll need to modify the LT1 wiring harness or check and re-pin as necessary the LT4 harness. Once it's running you have to account for the boost. If you use the LT1 harness you'll need to split the IAT from the MAF and possibly more.
You can copy the LT4 tables over to the LT1 tune.
For no-crank, double check the little black wire that goes to the negative battery terminal and that the positive terminal is tight. Test the various fuses on top of the battery. Lastly swap the fob battery and/or insert the fob into the slot on the steering column.
I'd strongly recommend you visit the HP Tuners forum. The Gen V section may have some better specifics and there are a lot of really sharp folks over there. Some do remote tuning and may be able to help. Jason is on this forum...@Internets_Ninja
