I have 1996 Chevy 1500. It is a V-6 4.3 L 2WD. I bought the truck about 1 year ago from a city, and have done nothing but repair it. I have bought a new alternator, 3 new fuel pumps, done a complete tune-up, bought 2 ignition coils, bought a new IAC valve, bought a new throttle sensor, and got a new fuel relay. I just went out to change my oil and noticed a burnt substance on the oil fill cap. It was orange in color. What could this be. I have had a rough acceleration or a hesitating exceleration, I keep[ coming up with a 300 code, but have changed my plugs multiple times. What could be going on?

 

I'm thinking that someone bought a 4.3! I'm not sure what's going on but to be honest I wouldn't buy a fleet truck if it meant the death of me