Replaced motor and now car starts by itself when battery is connected

MICHAELENE GRAVINE

MEMBER
2008 CADILLAC SRX
3.6L
V6
4WD
AUTOMATIC
85,000 MILES

The timing went so I had the motor replaced. After that it ran fine the first start up then it started doing weird things like; check engine light staying on when car was off and key was put, continues running after key is turned off and removed, and starting by itself once battery is connected. Can this be due to bad ground, alternator feedback, or ECU problem? Please I really need help!

Monday, November 4th, 2019 AT 6:51 AM

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
51,841 POSTS

Hello,

Yes, it does sound like a bad ground or ECU issue. To be sure lets do a CAN scan on the system scanners cost about $40.00 on Amazon. Here is a video to help us with the ground cable diagrams and connections in the diagram below. Check the second diagrams where is shows 2,3 that is the connection I would check along with the the cylinder head connection.

https://youtu.be/InIlnsjOVFA

Check out the diagrams (below). Please let us know what you find. We are interested to see what it is. Here is how you replace the ECU as well. If you get a rebuilt unit give them your VIN number so they can program it for you.

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