motor
 

Ok well my car is make a really loud knocking noise when it is running it sounds like rod knock but i cant tell. is there a certain sound it makes...o and it is a 1986 with a 2.8l v6

Has it been sitting for a long time?

Condensation in the gas tank=Water in the fuel=Knocking noise.

ya the guy said it was sitting for a year but it was out of gas when we got it and he just had the upper part of the motor rebuilt

I would wait untill Camaro 69 answers this question, the do what he says. :p

Did you giv eit a good tune up when you got it? new plugs, wires, oil, etc...

no i have only had it for 3 days now and i have hat to time to ordwe up plugs and stuff... but the guy was telling me that it might be a the pin the holds the piston head in place... so i am not sure

Ha, He seems to be the Seasoned man around here.

Here's something you might want to try. Back in the day we used to locate a bad rod by pulling off each spark plug wire one by one while the engine is running. If the knock quiets down abit on a particular cylinder then most likely thats the bad cylinder. Of course a bad rod means a trip to the machine shop. Also you might want to check your valve train for broken or loose parts. Good luck.