%&$#@!!! SES Light
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Joined: Jan 2003
Posts: 150
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From: harvest AL
%&$#@!!! SES Light
It was suggested that I post this here for ideas:
I could use some help with ideas why my SES light keeps coming on. The car received a new water pump and distributor cap/rotor, and new plugs about a year ago. The car has 40K on it and is stock. Ever since, the SES light will come on, usually after the car has sat for a few days. The light comes on blinking at first and then stays on steady (it will go thru this cycle a few times). Usually, it goes off by the end of the day and may or may not do it again the next day. The only code it ever reads is 0300 - random misfire. My Vette shop has more disgnostics stuff than any Chevy dealer and specializes in C4s. I trust them completely. He has run it hot, cold, and with diagnostic equipment attached while driving. Nothing comes up that is an obvious cause of the misfire. Everything has been checked multiple times. He has a complete computer baseline on the car so he can see if anything changes; and it hasn't.
Thanks, JCS44
96 LT4 Roadster, triple black
I could use some help with ideas why my SES light keeps coming on. The car received a new water pump and distributor cap/rotor, and new plugs about a year ago. The car has 40K on it and is stock. Ever since, the SES light will come on, usually after the car has sat for a few days. The light comes on blinking at first and then stays on steady (it will go thru this cycle a few times). Usually, it goes off by the end of the day and may or may not do it again the next day. The only code it ever reads is 0300 - random misfire. My Vette shop has more disgnostics stuff than any Chevy dealer and specializes in C4s. I trust them completely. He has run it hot, cold, and with diagnostic equipment attached while driving. Nothing comes up that is an obvious cause of the misfire. Everything has been checked multiple times. He has a complete computer baseline on the car so he can see if anything changes; and it hasn't.
Thanks, JCS44
96 LT4 Roadster, triple black
Instructor
Joined: Apr 2003
Posts: 149
Likes: 0
It was suggested that I post this here for ideas:
I could use some help with ideas why my SES light keeps coming on. The car received a new water pump and distributor cap/rotor, and new plugs about a year ago. The car has 40K on it and is stock. Ever since, the SES light will come on, usually after the car has sat for a few days. The light comes on blinking at first and then stays on steady (it will go thru this cycle a few times). Usually, it goes off by the end of the day and may or may not do it again the next day. The only code it ever reads is 0300 - random misfire. My Vette shop has more disgnostics stuff than any Chevy dealer and specializes in C4s. I trust them completely. He has run it hot, cold, and with diagnostic equipment attached while driving. Nothing comes up that is an obvious cause of the misfire. Everything has been checked multiple times. He has a complete computer baseline on the car so he can see if anything changes; and it hasn't.
Thanks, JCS44
96 LT4 Roadster, triple black
I could use some help with ideas why my SES light keeps coming on. The car received a new water pump and distributor cap/rotor, and new plugs about a year ago. The car has 40K on it and is stock. Ever since, the SES light will come on, usually after the car has sat for a few days. The light comes on blinking at first and then stays on steady (it will go thru this cycle a few times). Usually, it goes off by the end of the day and may or may not do it again the next day. The only code it ever reads is 0300 - random misfire. My Vette shop has more disgnostics stuff than any Chevy dealer and specializes in C4s. I trust them completely. He has run it hot, cold, and with diagnostic equipment attached while driving. Nothing comes up that is an obvious cause of the misfire. Everything has been checked multiple times. He has a complete computer baseline on the car so he can see if anything changes; and it hasn't.
Thanks, JCS44
96 LT4 Roadster, triple black
I have the same problem on my 88, replaced the MAF and the ECM, no change SES light still comes on and car runs bad. I suspect there is a loose ground on one of the relays or a bad wire somewhere in the miles of harness. It's too bad, these cars have decent engines and trannies, the electrical issues are the worst I've seen. Mine comes on and stays on after it warms up code 33 and 36.
