Major accelleration problem, HELP!!

[HiFlow5 0]

My buddy has a 99 S-10 PU with a 4.3vortech engine. He was driving yesterday and the truck started to buck, but went away. It eventually got worse over the course of 15 miles. To the point where it would idle fine, but once the gas was pressed it would not move. It would just buck and bog really bad and sound like the whole truck was going to fall apart. The battery light would also flicker on and off, but the volt gauge read 14 volts. Now heres the funny part. In reverse it would drive just fine, but put it in drive and the problems were still there. Today we disconnected the battery for an hour to reset the computer and added a quart of oil cause it was low. We took it for a drive and it drove fine, but the motor was still cold and not heated up to normal operating temp. Any ideas wold be great!!!!! Thanks, Craig

[GMANWI]

Have you checked the fuel filter? It may be clogged and this would restrict the flow of fuel to the injectors causing the engine to bog and buck.

Check the air filter and housing as your friend may have need of a new filter which might be restricting airflow and causing too rich a mixture.

And finally it may be the ignition module failing if the '99 has a distributor.

Hope this helps.

[Paperfish]

I had a camaro that did almost what you describe, minus the battery thing. It turned out to be the tranmission mounts...

[jdk2269]

Ok guys. Im making a check list. Thanks so much. 1. fuel filter CHECK. 2 Air filter NEED TO GET ONE. 3. Ignition module. How much are those? where do i get one? My truck has the same problems. We've done a FULL extensive Tune up. (oil, plugs, wires, cap, rotor button, and a new distributor)