HELP Low power cackle whats next
Still chasing down this slight miss low power issue with no luck so I hope someones wisdom can help me out here. I picked this truck up in bad shape very low on power. I hooked it up to my scan tool and seen that The ICP sensor was not reading and had a p1280 DTC . I replaced that and the truck ran somewhat better but still seemed to me down on power.
There was still what seemed to me to be a slight cackle with a miss so I tried a oil change which again seemed to quiet down the cackle a bit but still short on power. Then I get a low boss DTC p1247. I check all my CAC pipes take them apart clean the boots. I pull the intake and check the turbo wheel it felt good. I check the map sensor connection and it was good and readings on scan tool seem to be in line. So I decide to change the fuel filter.
Upon changing the fuel filter it was filthy and at the bottom of the fuel bowl and the pain i drained it into were little small shiny flakes. I clean the bowl out and replace the filter and do some digging on what those flakes could be. I read in another forum on here that someone said they had the same issue and it was the fuel pressure relief that was fluttering around etc scraping etc etc. So i go to the dealer get the rebuild kit replace it and seemed to run a lil bit better especially on power after a cold start. but still a slight miss and cackle but again quieter than before.
I clear all the codes drive it around for a few days and scan it again and I get the p1247 again . I do a buzz test and get the cylinder 8 code and do a cylinder contribution test which passes and says everything is ok. I planned on taking off the insulation on the intercooler pipe so figured i would pull the valve cover on the drivers side also. When I pull the valve cover off I notice someone has already put a half cut quarter on the harness and the plug was not pushed in all the way on one side I thought ahh my problem. I get it all tight put the valve cover back on etc etc.
I do buzz test again still saying injector 8 issue but as i have read this is common and yes i can hear it buzz durring the test. I drive it around that day and nothing seemed to have change still a slight miss which gets better as the engine warms up and low on power on inclines etc. I put it back on the scan tool this time I get a p1247 low boost and a p1316. I do the cylinder contribution test and get a p0263 for cylinder 1 which i never got before. So I think maybe i got some dirt in the harness or something and by harness I mean the one with the bolt in the center that goes to the other head. So I pull that off and spray some electrical cleaner in it let it dry and put some dielectric grease and tighten it back up. I do the contribution test again and this time i get a p0263 and p0275. I go back try to wiggle and play around with the wires and do the test again and keep getting the same two codes. there wiring didnt look to bad at the connector but I didnt peel it all the way back to passenger side connector.
There are a few things that come to mind but not sure where I should start.
with this just happening im thinking maybe a short in the connector is this common? Is it a sign of two injectors all of a sudden going bad? is this a sign of a IDM on its way out and how can i confirm I dont have someone that i can borrow one from. or is it possibly the signs of a bad CPS sensor?