[jdraupp]

My car was built in may of 2002. Not sure where that puts me, but I'm guessing DME 7.8?

Not having a durametric I can only go on what my indy said about my O2 sensors at the time and that was that the two pre cat sensors were not reading the same and the one he replaced showed high resistance. He recommended replacing the pair, however I opted to replace only the one that needed it the most as he was using Porsche o2 sensors and at 350 a pop, I figured I'd rather do the one and swap a bosch sensor in later at 88 bucks for the one that was not replaced.

My fuel trims are about normal. At idle, I'm seeing values between -3.0% and 3.0%. I don't have any fancier values than those, but I'm guessing they should be around that. However I should mention that at startup I initially got some sensor readings at 17 or 18% which I believe indicates lean? Is this normal on a cold start? When the car warms up and regulates idle the trims return to near zero?

I should also add this code does not show up until approximately 400 miles later. Both times this happened it was a long long drive and many starts before the code appeared. Removing oil cap on warm engine causes idle to change and car to bounce a bit, so can I assume that my vacuum system is in order?