Check Engine Light

I would remove the ingition module and have it tested, this is free at most autoparts stores.

First thing you need to do is read the codes, look under the dash and find the ALDL, this is a small diagnostic connector then do this: PROCEDURES FOR READING GM FLASH CODES
1. Turn the ignition switch ON but do not start the engine.
2. The "CHECK ENGINE" light come on indicating the bulb is working. If the light fails to come on, the bulb may be burned
out or there may be a problem in the Check Engine light circuit.
3. Locate the diagnostic connector for the computer. It is usually located under the instrument panel near the steering
column. Insert a jumper between the "TEST" and "GROUND" terminals.
CAUTION: Refer to a shop manual for the proper terminal locations. Jumping the wrong terminals may cause damage to the
computer system!
4. The Check Engine should now flash. The first code should be a code 12 (Flash, Pause, Flash Flash). Code 12 will repeat
two times.
If any other trouble codes are in the computer's memory, they will be displayed in numerical order starting with the lowest
number, and repeat three times. The codes will continue to repeat as long as the test terminal remains grounded.
NOTE: BE SURE TO WRITE DOWN ANY CODES THAT ARE PRESENT
NOTE: GM may use the same code number for different faults on different models of vehicles. That's why some code
numbers list more than one possible cause.
5. To exit diagnostic mode, turn ignition switch off and remove the jumper.
HOW TO CLEAR TROUBLE CODES
Trouble codes on most older vehicles can be cleared by removing battery voltage from the computer for at least 10 seconds.
Make sure the ignition switch is OFF, then remove the computer fuse from the fuse panel. Disconnecting the battery will also
work, but doing so will also cause the loss of stored information and presets in other electronic accessories such as the
radio, climate control system, memory seats, etc. Disconnecting the battery can also cause the computer to forget long term
fuel calibration adjustments, and may affect the operation of an electronic transmission until the computer can "relearn" the
shift points.
The preferred method of clearing trouble codes is to use a scan tool.
Page 1

Intermittent issues can be a pain to track. You have to test when the problem is ongoing. Because the crank and cam sensors share ref voltage and ground, I'd have to check the crank sensor also.

If you live in a state that doesn't do vehicle inspections and no driveability issues? My state hasn't done vehicle inspections in years.

Looks to me like you got it all covered. Using the epoxy is fine, I've never used it on the magnet, itself?