I took out my heater sensor on my 2003 Chevy Impala but the new one will not twist back in what do I do

SOURCE: Have a 2003 Chevy Impala. Check engine light

Bank 1 is the rear O2 sensor, but experience says to change both. The front one is right behind the engine in the middle of the engine compartment. The rear O2 sensor is on the top of the exhaust pipe, just behind the catalytic converter. But the same code that shows it is the O2 sensor (which is P0420), is the same code for the catalytic converter, or a vacuum leak. Make sure if you do change the catalytic converter, ensure that the new one is OBD-2 compliant. And the vacuum leak could possibly come from the manifold gasket. Let me know what the problem was!

SOURCE: serpentine belt diagram for 2003 chevy impala

send an email to [email protected] and I will send the diagram to you

SOURCE: 2003 Chevy Impala transmission

my 03 impala only jerks hard when the engine is cold or slightly cold. when its warm its fine. i never had it looked at before.

SOURCE: Replaced ignition switch 2003 chevy impala and car will not start

After you replace the ignition switch turn the key to start the car and release leave the key were it stops after trying to start wait 10 minutes until security light goes out turn key to full off position then repeat the above procedure two more times for a total of three on the 3rd attempt to start car wait for light to go out then turn key to full off positoion wait 10 seconds then try to start car body control module should learn new pass code and the car should start.
Big john, J@J Automotive

SOURCE: Where and how many o2 sensor's on a 2003 chevy impala?

There are two sets of 02 sensors on most cars today. On set is set directly behind the header, one on each side, if it is a V engine. This set is used for the engine's ECU to control timing as well as other variables. The other set is placed on a bung in your Catalytic converter. This 02 sensor is used for emissions purposes only.