Ok, its me again with my 1989 Chev pick up. V6 engine.

It runs great except when I start up hill. then it misses and runs rough till I give it a lot more gas and then it sort of jumps and does fine as long as I hold the gas pedal down.

. Replace spark plugs, with the exact ACDelco plugs that came in the truck. If the distributor cap and rotor haven't been replaced in 60,000 miles, I would replace them.

. Replace fuel filter.

If the problem persists, replace the Ignition Control Module (ICM) and coil:

http://www.autozone.com/autozone/cat...hText=ignition

http://www.autozone.com/autozone/cat...earchText=coil

It wouldn't surprise me if the ICM is the culprit. They are a problematic component ("electronic points") that should be replaced every 120,000 miles or 10 years, whichever comes first. It may be breaking down under load. Neither the ICM or coil are expensive for your truck and are easy to replace. Replacing these items would help ensure the integrity of the basic ignition system.

Distributor cap and rotor, most likely same after 250,000 miles will try that.

I had a similar problem and it was a spark plug wire.If the above suggestions don't work I would try replacing them.