2003 Blazer this last weekend made a trip to/through/and back to the KC KS area. Probably got some dirty gas at the station in MO that I got a free opossum with a fill up. Anyway the next couple days were darn hot, the Blazer had no energy, it got around but the shift points were way off. It would down shift two times just to go up a slight grade at highway speeds.

Example if cruise was set at 65mph, and I pushed the accelerate button on the cruise 10 times to kick it up to 75 it would have to shift down two gears to make it.

Another example was if going 75 and enter a construction zone, I would hit the down button 10 times it would slow down to 60 then have to shift down a gear to get it back up to the intended set point of 65.

Wanted to start with a fuel filter, could not break the fittings loose so I took my new bought filter and took and had it changed. Life is back in the Blazer all is good.

Speaking of setting service codes would a scanner have indicated a lean condition without setting a check engine light?