[obadran]

I almost have a similar problem with my 96 yukon with 100500 miles on. I would have intermittent extra long crank times to get the truck started and also a lack of power on moderate to full throttle acceleration. I eventually, under a full throttle accelaration got the check engine light to come on. The codes pointed to my o2 sensors and that the o2 sensor were detecting a lean condition.
I took it to the dealer and explained everything along with the fact that I have to replace my fuel filter every year to avoid stalling due to a plugged filter.....Summer of '03, I was stranded on the PA turnpike 5 hours from home due to a clogged fuel filter. Long story short, they found 'stuff' floating in my gas tank....I got a full fuel system cleaning/flushing from the injectors all the way back to the gas tank. For the most part the problem is solved, but I still think something else is wrong and it's probably something electronic so I guess I'll have to wait until it dies completly.

In the fuel tank, the fuel pump has a filter screen and if it is clogged you will get reduced fuel flow. With 168K miles on your truck, I wouldn't be surprised to find 'stuff' floating in the tank. 168k is a lot of fill up at the station.

Hope this helps