i have had some injector problems for sometime now. the dealership couldnt find anything wrong with my truck so i took it to a good local diesel mecanic. my truck dosent throw any codes and it shows that all the injectors are working properly, but there sometimes is a loud knocking sound coming from the pass. side of the motor. the diesel mech. hooked up a box that allows him to cut out one injector at a time and he found that when he shuts off the #3 injector the knock goes away. he said it might be something in the lower end or just a bum injector, but if it were in the lower end wouldnt it male the noise all the time? has anyone ever heard of something like this? the truck does blow some white smoke at idle on occasion. any advise will help. thanks

 

Injector. If it's blowing excess fuel and knocking it will make smoke.

 

You also could have an electrical harness problem interfering with the injector functions double check all your harness connections and glo plugs use an ohmeter, it's not uncommon for harnesses to melt down inside the valve cover, the gloplug leads melt and compromise the injector connections, check all electrical first, and my truck thru no codes. tried to put a pic or two here e-mail me if you want those

 

injector problem, my buddy had the same injector do the same thing

 

I would lean toward injector too as i had a similar problem last summer.

 

does the injector really make a noise like a rod knock when it is bad? i am kind of new to this diesel thing and the dealer is giving me the run around. thanks guys.

 

A lot of times. Or a dead miss. Once you've heard an injector knock you'll swear it's spun a rod bearing.