Need help & educated on tunes.

[PuroCumminsPower]

(08-24-2021 )Mr Hagg Wrote:  Rocking most of the time is from a missfire. Either weak Cylinder, weak injector, wiring harness, and even bad ecm if drivers inside ecm are bad.. Like rawze mention before check for leak down to make sure no injectors are leaking. You can do cylinder cut out to see if any you cut out stops the shake. And go from there. You can all on cold start up check cylinder temps you will see if all are firing the same.
Strange this I had the other day was had one running rough and I would have bet $1000 that it had a bad injector or weak compression. The jakes started acting funny during test drive to i installed 2 new solenoids. Test drove did the same thing. So I started looking at the injector/Jake harness looked ok but was slightly wet with oil. I went ahead and replaced harness. And wow... thing ran like a top. Engine had a slight fuel knock before too and that was gone too..So there's a few things to check for... With Rawze's (I use his recommended settings) idle timing is perfect and runs smooth every single time for that model engine so if for some reason its not smooth need to look somewhere other than tuning...

Good evening Mr Hagg. Can you please give me the part # for the injector/Jake harness? My trucks engine brake with Cummins 871, in the last 2 months or so started not working to well. It isn’t working like it should. I have a feeling it’s the harness.