Engine/Transmission (1998.5 - 2002) P code went away

[Tractorat]

Has anyone ever had this happen ? I had a code appear the other day when I clicked the key over 3 times. I was getting ready to take it to the dealer to have it checked out. But, just before I got there, I checked it again, and it was gone.



So, before going back to the dealer where they would charge me $100 and tell me nothing, I took my truck to my regular mechanic to scan the truck with a regular scan tool. Nothing came up. And I think he said the last time the computer was cleared was 250 cycles ago. Just to check myself, Im going to have my son-in-law, who is a Mercedes diesel mechanic check it with his scan tool as well. But, Im sure he wont find anything either.



Has anyone ever had this happen before, where a code just disappears with no trace ?



Thanks,

TRat

 

[Tractorat]

Guess I must be the only one thats ever had this happen

 

[Mundgyver]

No your not. What happens is if the engine sets a code and it is valid, it will stay on. If the condition that caused the code corrects itself or if it was an erronous input causing the code and does not re-appear or set again for 40 start cycles, then the code will clear on it's own.

 

[Tractorat]

Thanks for the reply. It was the 0216 code. Even though it disappears from the "3-key click" check, everyone Ive talked to says it should still be in the computer. And that a real computer scanner should find the code. However, its not there either. Im trying to decide if the code should really have been set, or if some external occurance may have caused it to set, then unset. Its a mystery