Cadillac Repair: 90 deville 4 door check engine light is on, Los Angeles Plaintiffs Forensic Locksmith, Miami Plaintiffs forensic locksmith

Question
hello,

The check engine light is on after i put in gas ? I was thinking i was putting in the wrong gas so i uped it to 91 octane premium. the light went off after driving for a while then came back on . The car runs fine. Just when I get gas it comes on then off again and sometimes it stays on for weeks . I read your other replies so i tried the check engine test and this is what came up : 8.8.8 E48 E52 .E.E E48 .7.0  then i pushed the econ button then F.8.5 came up  . can you please help me? .....

Answer
Hello,

I have no such replies. It has been far too long since I worked with that computer system to accurately tell you how to get the diagnostic codes. The system was changed in 1994 to the OBD II standard which is completely different in a 1990 GM vehicle. All I remember is to cross two wires on the computer port under the dash and the code would be displayed by the number of flashes in the check engine light. If the light stayed on and then blinked 4 times that would be a code 14. Then one would need to see what code 14 was in the service manual and then the diagnostic and repair process could be engine.

Your car will run great until the emissions light (check engine) light illuminates. At that time it is not running in what is known as closed loop and the engine will get bad gas mileage while emitting emissions.
As for the terminals to be crossed, I no longer remember, but a local service center may be able to assist you.


This system has not been used since 1993.

Good luck!

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