Ok my truck started making a weird noise or miss sound after making a long trip and back home. It's only done this that once that I know of. It's got the loping at idle and has had this for a while but what I heard was a distinct thud sound like it hit harder when firing in a cylinder, then the normal idle and then it hit hard again and did that a few times... what could this be?

I've had the injector harness replaced by the dealer probably 50,000 miles ago. I might need to ice pick this one???
Fpr switch crapping on on my injection pump??? How do you log this with EFI live to test it?
I checked the balance rates and everything was all within the +4-4 range if I'm reading into things right... most were say .67 as an example while one was -1.97 and another was +1.56. so the way I'm thinking these are still good correct?These number are only examples and the only parts of them that are correct are the -1. and +1. I data logged them and can't remember the exact numbers. I hope that didn't confuse people to much.

Could there be anything else I'm over looking if these things turn out to be ok? Thanks

wow nothing with this many views? Well I'm starting to lean towards FPR if my injectors are ok with what I posted. May try to ice pick my connectors this weekend if it'd ever stop snowing. I'm sure someone will chime in sometime.

From what i understand, the truck will run like crap if it needs the ice pick fix. The FPR may be weak, how many miles? Mine has 236,000km and it has the shaky idle, but i don't know if would cause a sound like your describing. Im sorry im not more help.

From what i understand, the truck will run like crap if it needs the ice pick fix. The FPR may be weak, how many miles? Mine has 236,000km and it has the shaky idle, but i don't know if would cause a sound like your describing. Im sorry im not more help.
Alright, thanks... Trucks got 110,xxx miles... any helps better then no help.

You will need to log demanded fuel pressure vs actual fuel pressure. In the log they should be very close to one another. If the actual is swinging a lot at idle then the FPR is typically the culprit.

OK looking at things a lill closer in the log. This is what I've found.
#1 2.17 max
#2 0.72 max
#3 0.80 max
#4 -0.40 max
#5 0.47 max
#6 -0.04 max
#7 -1.68 max
#8 0.11 max

actual fuel rail pressure max 5944 psi
desired fuel rail pressure max 5947 psi
Difference between actual and desired fuel rail pressure 432 max.

well this seems to look ok to me what's you guys take on it? if it's ok any other ideas? Thanks

Through some cleaner in the diesel and see if that helps, it could be just some bad fuel you picked up somewhere.

Your injector rates look really good and so does your actual vs demanded. So not injectors or FPR.

Do the ice pix fix