I was inspecting a 2011 Volkswagen Jetta today and saw on my OBD reader that it had two misfire codes, if I remember correctly P0302 cylinder 2 misfire and P0300 multiple cylinder misfire. The check engine light was off. The seller had just mentioned her husband replaced the spark plugs within the last year and I asked if there was something that prompted him to do that. She said that the engine had been misfiring and the problem went away after he replaced the spark plugs.

I wanted to clear the codes and run the engine to see if they came back, but after asking the seller's permission and running my OBD reader's "Erase Codes" function both codes were left. I noticed they were under a heading called "Permanent Codes." Is there any way to erase these codes or are they really meant to be there for the rest of the life of the car?

1 Answer 1


Yes but the module itself has to clear them, not your scan tool. If the codes where still there then there was still a fault in the system or it has not met the conditions to remove them yet.

  • 1
    This seems to be correct. I bought the car yesterday and have driven about 40 miles since then with no issues. I checked the OBD codes again today and the permanent codes are gone.
    – zaen
    Jul 1, 2020 at 0:39
  • Nice, congratulations! and thank you for the update.
    – narkeleptk
    Jul 1, 2020 at 1:16
  • Actually that's not true, you can get them to clear by starting a diagnostic session with the module and not using the generic OBD2 clear function. It all depends on the tool that you are using, for this platform I would recommend VCDS.
    – Damon Earl
    Jul 1, 2020 at 1:54
  • VCDS is indeed an excellent tool for vw's.
    – narkeleptk
    Jul 15, 2020 at 0:59

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