I have a 95 k1500 stepside with a 350 all stock as far as I know.
It has a 5 speed manual transmission.


So I bought this truck 2 weeks ago and it started knocking yesterday, it doesn't do it when it's cold it only starts to knock once it gets to operating temp and if I accelerate it will do it until it hits about 2000rpm's
It does it in neutral and in gear and it doesn't matter if the clutch is in or out. It was also running very rough so I replaced the spark plugs and it doesn't run as rough but its still running alittle rough.
Spark plugs were coal black when I took them out.
I also just noticed alot more fuel smell in the exaust but it doesn't have cats so i may have just not noticed it before now.
Any ideas would be greatly appreciated
Thank you.

 

When were the oil and oil filter changed? Does it stop knocking after 2000 rpm? To get rid of the rough running you might also need to change the spark plug wires, rotor and distributor cap.

 

i was told the oil had about 3000 miles on it and upon inspection it didnt look too bad. but i have no way of being certain as i just bought it.

i can no longer hear the knock after around 2000 rpms.