88gmc 1500, it dont have no take off power, but once it warms up it goes, but once I slow down it is hard to pick up speed again. I have changed spark plugs , wires,cap & rotor, fuel filter & o2 senso
Have you checked the fuel pressure and flow? There is a fuel strainer inside the tank that can get plugged up. There could also be a sensor misread for engine control, have you had a sensor scan performed?
Scotty, it sound like it's your tranmision as if it is starting in 2nd gear. i would start looking there first since you did a tune up on it.
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