I figured out what the awful “coughing” noise was. I have the off road Y-pipe going to a single muffle out the side in front of the driver tire. Right where it exits I have a chrome splitter. It looked nice but for some reason it wasn’t jiving with my set up. Best way I can describe it. Thanks and maybe be this can help somebody down the road

SO cutting THe muffler tip just made the noise quieter, for a little bit. It got progressively worse. I bought a temp gun and checked the temp at the primaries on my headers right next to the head. Cylinder #1 was 615 degrees fareinheight! The others were mostly under 500. I tore it all down and saw heavy build up of carbon on the Pistons. Also oil in the intake runners. Scrapped and cleaned it all off. Took the heads to a local machine shop to have them inspected and they checked out ok, minus some heat signatures on my exhaust valves, they were “rainbowing”. Put it all back together with brand new baskets of course. Installed a catch can. Cranked it back up and the horrible noise was gone but the temp of the primaries was still the same heat. This is way too hot and I don’t know why. I’m going to have it retuned In the immediate future. I did do a compression check and they all had 210psi except #2 which was 200. It has a Stumble upon cold start. Any ideas?

I had a couple guys, two with tuners, look at it. The long and short term fuel trims were said to look good. I had my injectors bench tested. They were good. I’ve got 60 psi at idle on my factory fuel pump with 187k miles on the truck. It’s been a headache to say the least with this motor swap . But I’m definitely getting my truck back to the tuner!