I have a code for #6 low contribution and a thumping noise out the exhaust. When I turn number 6 injector off the popping/ thumping goes away. Truck is straight piped and deleted. It started doing this after getting on it hard to get on the high way. Sounds like beating an empty pop bottle on something

 

Is your engine a 6.0, or a 6.7?

 

This one is A 6.7

 

If you can turn it off, can you also test fuel balance on the injectors? Does it show abnormally higher or lower than the others?

 

I may be able to. I have a snap on Solus pro. What should I look for.

 

There are others with far more talent than I have that could better assist, but I would look to see if it is abnormally higher or lower rates when compared to the other injectors. To me, it would either be a bad injector, or something with the piston, wrist pin, or connecting rod. Let's hope it is an injector.

 

The noise goes away and truck sounds normal at anything above idle also. With that injector turned off it sounds normal at idle. Where should I start looking for the problem. And actually I just checked and my scanner is a Solus edge

 

Could an injector firing incorrectly cause a noise like this?

 

I would still check injector balance as the starting point. Maybe it is skipping the pilot injection on that single injector for some reason.

 

I looked through the scanner and I don't see a test for that. I do see cylinder contribution though

 

The truck also feels weaker than it used to be if that helps to figure it out

 

Hopefully someone with more knowledge on the subject will be able to jump in tomorrow and assist. If it quiets down above idle and isn't smoking, I would like to think it is ok to drive until you get better info.

 

Yea. It's a pretty strange issue. I was thinking it was rocker arm/ push rod related until I turned the injector off and it stopped. Now I don't know. Maybe a should just pull that valve cover and have a look. If everything looks good then throw in a number 6 injector and see if it fixes it

 

If and when you replace an injector, remember that you have to connect to IDS to enter the calibration code for that new injector into the system, or it will throw a CEL.

 

With a good enough scan tool you may be able to program it without IDS. Good luck and let us know how it turns out.