93 Chevy 1/2 ton WT with 4.3 V6, automatic. 81K miles. excellent
condition and maintenance.
I know it's never going to be a tire smoker, but I owned a similar
truck years ago (recently bought this one) with a lot more miles that
Truck runs nice and smooth. Internally, engine is in good condition.
I had my reliable independent mechanic
try to fix the driveability problem to no avail. So far...new plugs,
cap and wires, everything checks to specs on diagnostic machinery.
FI serviced, engine de-carboned (apparently some old GM TSB).
New fuel filter. Has new K&N air filter.
Truck is still a dog on the freeway, especially with the AC on. In
fact, it is so gutless I am afraid to pass anybody if it requires me
to go more than 70MPH. It also has what I consider poor throttle
response off idle. If I drive it like I stole it it's OK but at low
throttle it stumbles. At full throttle it seems to run fine all the
way up through the gears. In normal driving it sort of feels like the
timing is not correct, especially at higher RPMs. With the AC on it
seems to lose all desire to pull. The slightest incline will cause it
to slow down dramatically and start hunting for another gear.
Any ideas? I hate to take it to a dealer or another mechanic but I'm
close to doing so.