Hi everyone.

2003 Monte Carlo ss, 125k miles.

Wife took car from NY to Florida and back. On way back the car 600 miles into her trip, car would not go past 15-30 mph without bogging down, bucking and not going any faster. Car had been tuned up with new plug wires, plugs, new breaks, oil changed, new Cat about 3 months ago. I had her take car to mechanic when in Florida just to make sure everything looked good for the trip back up to NY. No engine light came on. She made it home and I let the car sit for about an hour. I checked all fluids and all are very clean. Took for test ride and all seemed fine.

Anyone have a clue on what she experienced.

Thanks

KJ