QuestionMy truck is having an occasional hesitation problem that I'm hoping you might have some advice on. The details on my truck:
1995 Full-size Chevy truck (C1500 Cheyenne 2WD)
4.3 Liter V6 - Manual transmission
117,000 miles
The problem is that occasionally, the truck will hesitate while I'm driving. The hesitation has occurred while driving on the freeway as well as side roads. Specifically, while I'm driving, the truck will completely hesitate for a fraction of a second (usually throwing me forward in my seat) and then return to normal. When the hesitation occurs, the check engine light does not come on. The best way to describe the hesitation is that it's almost like turning off the truck and then quickly turning it back on. When the hesitation occurs, it feels like the truck loses all power but the radio and other electrical items still stay on. One of the most frustrating things is that it's so random. It might happen once in two weeks and then it might happen once a day for a couple days in a row. Then it might go a couple more weeks without happening. The hesitation does seem to happen more often when the air conditioning is on or if I'm climbing a steep hill and I don't downshift to a lower gear (e.g. downshifting from 5th gear to 4th gear).
In terms of what I have already done:
- Approximately 20,000 miles ago, I replaced the spark plugs, spark plug wires, distributor cap, rotor, fuel filter, transmission oil, thermostat, upper/lower radiator hoses, antifreeze, and battery.
- Cleaned air filter (K&N filter).
- Originally thinking that it might be an AC problem, I had my local Chevy dealer inspect the entire air conditioning system. They said that it was operating correctly and that the hesitation (which a technician did feel during their test drive) was due to the age of the truck and that I should "just live with it." This seems like a problem that should be fixable and I don't want to live with it.
- I talked with my local general car repair shop and they told me that unless the hesitation consistently occurs, they would be taking my money because it would be difficult/impossible for them to root cause the problem.
I have taken extremely good care of my truck and I would like to keep the truck for many more years. Any advice that you could provide would be very much appreciated.
Thanks,
Shane
AnswerIntermittents are the hardest things to find. Other than the most obvious:
Plugs, injectors, egr system, plug wires, dist cap, rotor, intermittent electrical connections, fuel starvation, fuel pressure problems, faulty fuel injector circuitry and numerous others, I have found many vehicles that had a flat spot within the TPS (THROTTLE POSITIONING SENSOR) of which did NOT illuminate the check engine light on the dash.
