Camshaft position sensor.
my 03 corolla started acting like it was misfiring, then it started stalling. Each time it was harder to get it to restart. codes were read said camshaft position sensor and ignition module errors. What can I check to make sure which is wrong, and can one cause the other to show error while still fine?
Normally the Cam Position Sensor can cause other erroneous errors. It could be tested with a volt meter to ensure it's functioning properly. Quite a simple test. If you can't do that, the sensor is cheap, I'd replace it first.
If this is a coil on plug configuration, you might want to test your ignition coils. This can be done several ways. Remove the coils one at a time and check the resistance across the primary and secondary windings. Then you can test coil output with a coil tester available at the parts store. One bad ignition coil can cause this problem and "false" codes to set in the computer. I would be inclined to clear all the codes and see what comes back. Good Luck codes
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