Q: Check engine light appears and disappears

asked by on December 06, 2016

check engine light appears and disappears computer reads oxygen sensor

My car has 100000 miles.
My car has an automatic transmission.

Sometimes when a check engine light comes on it will set a code in the computer and if after a set time limit the problem does not repeat the computer can turn off the light and go back to normal operation. The code will still be in memory so diagnostics can be done on the failing circuit. This is an intermittent problem and a problem may not be found at the time of testing. The code should be noted and cleared to see if it returns.

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