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Can't clear check engine light

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I ran some Seafoam thru my PCV to clean things out a little. The car runs smoother but the Check Engine light is lit, no doubt to the extra solvent. I tried to clear it with my code reader, but I just keep getting an "E". Is something wrong here (it works on my other cars) or is there another way to clear it (battery disconnect)? Thank you.

Just unhook the battery for an hour or so. Or leave it overnight and hook it up in the morning is what I do sometimes. Are you sure you don't have a problem causing the code to set again as soon as you clear it?

Was this done for general maintenance or did you have a drivability concern before hand? Also was the CEL on before the seafoam?

  • Author

No CEL before treatment. On my other cars is usually would be an O2 sensor or EGR code, that doesn't reappear after code clearing. I'll disconnect the battery and see what happens, but I wish I new why I can't scan codes.

No CEL before treatment. On my other cars is usually would be an O2 sensor or EGR code, that doesn't reappear after code clearing. I'll disconnect the battery and see what happens, but I wish I new why I can't scan codes.

 

When my O2 sensor went bad, a code reader couldnt read the code either, and wouldnt clear it. This happnes sometimes. Disconnect the battery clear the code then next time it comes on read it.

 

How many miles ?

 

 

nipper

  • Author

How many miles ?

 

118,000. And I did mean to say "knew," not "new," previously. I must be getting a Check Brain light:-p

If the CEL is on there should almost deffinately be a code in the computer. Did you try to read them? If so what was it?

If the CEL is on there should almost deffinately be a code in the computer. Did you try to read them? If so what was it?

 

Not necassarily. The O2 sensor on my car was alwyas activly setting a fault, so if you tried to clear it the data would get all confused, and no code was set. Now if i read the code fist thing in the morning then i can read it.

 

You need to use the code reader a few times a day, especially after a cold start, and you may be able to snag the code.

 

Also a differnt brand code reader may do it. Snag the code right after you disconnect the battery for an hour.

 

hopes that helps.

 

I wouldnt be surprised if its the front O2 sensor. That can be tested with a multimeter if we still cant get a code off the ECU.

 

nipper

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