For the first time in the history that I have owned this car 114,356 miles all together the Blazer has thrown its first code. Yesterday while driving back from running an errand it threw at PO440. Did a little reading here and elsewhere that seem to indicate that the gas cap was the culprit so I went andpicked up a new one. Cleared the code and now we will wait and see if it returns. The new gas cap went on with a little more effort than the old one so I hope that is the fix. I do not smell gas at all when it is either under power or just sitting.

We will see

Regards
Don