Hello all. I have searched the archives but cant seem to find anything that i think is related to my knock that i'm experiencing. So i have a 95 k1500 that i bought a while back. It has a 350 out of a 91-92 dump truck. It is a tbi. So anyways when i bought it the engine had a miss i changed spark plugs wires and then narrowed the problem down to my distributor which was shot. I put a new distributor in. It ran great after that drove it down the road and back and noticed a knock. Now even though thier was a loss of power before the new distributor was put in, and by loss of power i mean i couldnt even make it up a hill in anything other than 1st gear, Thier was never a knock until i put in the new distributor. Now i had my uncles helping who are 350 small block old heads lol. SO of course rather than following my timing marks they just plopped it in and we turned the distributor till it was running. Wasnt the way i had planned it but thats family for ya lol. Anyways i started reading the gm factory manual i had for it which says when you time it, and this is based off timing it the correct way with a timing light, that you have to unplug the icm switch that runs to the ecu. So i did that retimed it the same way we did before and whatta ya know the knock quit. So i had it running for about 20 minutes all was good reved fine no noise. Then i plug back in the icm start the truck and welp knock starts up again. NOw the reason i'm posting this is i still believe i have some kind of spark knock one way or antoher or its in relation to the icm plug. but whats wierd is when i unplugged that plug again the knock is now still thier. So i guess what i'm asking is do i have a spark knock or am i experiencing a motor knock when the vehicles warmed up? Its just odd to me that the knock wasnt thier until i replaced my distributor. Thanks to all who view and any insight is greatly appreciated.