> My 88 B2600 starts ok and runs fine at slow speeds.If I try to go over
> 60mph it almost shuts down.
> I have replaced spark plugs and wires and a new distributor cap, but
> still have the same problem.Does anyone have any suggestions for fixing
> this problem?
Why do you think the problem is related to the ignition system? Your
descriptions sounds more like a fuel system problem to me. Have you changed
the fuel filter? How about the exhaust system? A plugged exhaust system will
casue similar performance problems. How about the air filter?
Ed