Every so often I'll be driving do the road and feel a slight drain in performance. The only way to correct it is to let off the gas, or go wide open. It can happen at any time, except for cruising speeds. Take off, around a turn, ect., it happens. Almost as if I'm running lean or rich. I'm suspecting the TPS (Throttle Position Sensor), but it could also be the injector connector clip slipping off. However, if it was the injector clip, it wouldn't correct itself most likely? Any other suggestions on what the sluggish performance may be caused by? I can provide more details if needed. I know it's a very vague description, but don't have any other way to describe it off the top of my head. I have searched this (first 3 pages in search and on Google). Which leads me to think it's most likely the TPS.

No CEL, 238k miles, recent tune up, engine idles fine and revs fine.

 

Is it a TBI or CPI engine? When was the last time the fuel filter was changed? It does sound like a fuel delivery problem to me? Could be a fuel injector going bad? You could try a can of sea foam in the gas tank. It could be the TPS, if you have a scan tool you could monitor TPS voltage output to see if it is working correctly. Another thought is the O2 sensor not performing correctly. The computer uses the O2 sensor to adjust fuel trim.

 

It's TBI. No idea when the last time the fuel filter was changed. I just recently bought the Blazer. Already ran SeaFoam throuh it. Partially through the gas tank, and partially through the intake. I don't have a scan tool, but can easily pick one up. Any suggestions on one?