How to rekey a pontiac sunfire 2004 - 2004 Pontiac Sunfire

Im assuming you are refering to the anti theft security key relearn process.

1. Perform a security system relearn.
2. Let the vehicle sit for more than 10 minutes with the key off.
3. Attempt to start the engine, leave the key in the run position monitoring the security system indicator.
4. After 10 minutes, the security indicator will change state.
5. Turn the key off and wait 10 seconds.
6. Attempt to start the engine. If the engine stalls, wait another 10 minutes with the key on.
7. After the second 10 minute timer has expired, turn the key off for 10 seconds.
8. Attempt to start the engine. If the engine stalls, wait another 10 minutes with the key on.
9. After the 3rd 10 minute timer has expired, shut the key off for 10 seconds.
10. The security system will relearn on the 4th starting attempt and the engine should start and run.

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