What a great thread! I can attest to the sputtering after fill up, which I attributed to bad gas, but I also almost stalled coming to a hard stop as well. I thought that could possibly be the clutch or dual mass flywheel getting old. Last week I got a check fuel filler light on the dash and did a quick search... Of the three issues one being the cap less filler being dirty was the Canister Purge Valve mounted on the intake next to the throttle body. I did a quick test and found it had failed and was sucking in excess air causing all sorts of problems. A trip to Autozone revealed that the Duralast part is a Fomoco original at $29 with a lifetime warranty! It went on in two minutes and my idle is now rock solid and I'm going to say improved throttle response through the good old butt dyno. Anyone with the bad idle or a check filler light or even bad 02 message should check this, the excess air or fuel throws off the computer and can create rich or lean conditions resulting in poor economy and performance and possible false 02 codes.
You know that warm and fuzzy feeling? That means something bad is about to happen...
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