2003 Alero, 3.4L V6 118,000
Been having a problem for about 3 weeks now. The car intermitently lacks power, mainly below 3,000 rpm. Most of the time it will hit 3,000 and its like switch was flipped on. Plugs, wires, fuel filter were all changed 18,000 ago. Intake gaskets were changed last weekend, along with the trans service, the second one I've done to it. There is no check engine light either. The engine does not have to be put under a load (hill), and temperature does not affect it either. Sometimes its completely normal though, I can't put my finger on it and would like to here what you all have to say before I take it in. Wish I had the equipment to do it myself, I used to wrench at a Lincoln-Mercury Dealer so I'm familiar with cars. Thanks for the help!!

 

Maybe a cracked or fouled sparkplug, or maybe the plug wires have rubbed against each other or the engine?