3406E With a stumble/miss - sometimes

6TS 3406E and I just got done replacing all the injectors in. New fuel filters, and I can still feel a vibration sometimes under partial throttle about 1400-1500rpm. Over head was ran when we did the injectors.

I left the house the morning and made it to my destination about an hour or so away and the truck ran absolutely perfect. Sat in the grain line for about 3-3.5hrs and idled the truck up to 900rpm while sitting still. By the time I left the truck was running rough under partial throttle with the vibration. It has a tick to it when it starts acting up, the sound reminds me of an exhaust leak kind of sound but I cannot find soot anywhere.

Any ideas of what and how to check would really be appreciated. Ive been banging my head on the steering wheel chasing this problem for far to long.

 

Sounds good, my mechanic is an independent and is pretty good with CAT's but actually thought and had me run the overhead. Like I said the injectors are all new, but I've heard of stranger things than a new part thats bad. I will get a gage on it first. Thanks for the help. Dang thing is just frustrating.

I did forget to mention I am NOT down on power at all

 

Perfect thank you. I still need to get a pressure gauge on the thing, Been stupid busy. But yes it had the vibration/ stumble before the injectors but can't recall the tick as much. All great suggestions and will look into them.

 

@E model Cat man I went ahead and replaced the check valve on the fuel block being the compressor and no change. When I was down to 1/3 tank or so of fuel I can hear the fuel returning into the tanks with the caps off, sounds like you're taking a leak in a puddle so Im guessing that it is returning fuel alright. But I still need to get a gauge on it. Just curious what ports to use to check the supply and return pressure and where the pressures should be at.
the check valve I replaced was the one on the bottom that takes a 1" wrench, hopefully that was the correct one. Also what kind of threads do I need for the pressure gauge to hook to this thing, do you us an adaptor or is there one that can be hooked straight to it.