So I've been plugging away trying to figure out what is going on with this engine. (1998 Wrangler SE with a 2.5L) It's been running like crap and doing a ticking/knock during idle it's also really sluggish while acceleration, feels like a misfire; reminds me of times I've gotten water in my fuel. Had the codes ran, its throwing a misfire on #1 P0301& a CAT code p0420. I did a compression test and it was surprisingly all within specs; #1 one was a little low but still within a 15% difference. (#1) 140 (#2) 150 (#3) 150 (#4) 155-160. I also did a leak down test; #1 was 9-10% the rest were 5%-8%. I also noted that during the leak down, cylinder #1 made the radiator fluid rise and over flow. I changed the head gasket not too long ago. (unfortunately I didn't check the mating surface for flatness)
I guess my question is, would a warped head give these type of readings and make the engine perform in this manner? Would this also make cylinder 1 knock or is that something else?