i have a 89 d350 cummins that i need some help with,it has a small knock,and it missis,and white smokes i think its an injector but im not sure can anyone help

 

sounds like injector to me

 

Could be a bad injector, a fuel leak, or even a Blown Head Gasket.

Start the truck up and one by one crack the fuel line nuts on top the injectors and see which one makes th least amount of difference in the way the engine runs. that will point you at your problem injector or cylinder.

Oh and

 

it sounds like most of the nock is comming threw the air filter

 

have you ever adjusted your vavles they might be out of adjustment

 

yeah if you have a pulse coming out of the intake chances are one of your intake valves isnt closing all the way whcich would make me check the pushrods


keep us updated

 

it was the valves i ajusted them according to a chilton manual and that seemed to fix it,but i broke my timing pin in the process but it was the valves thanx

 

Fixed according to original poster