What I'm seeing cylinders 246 and 8. Are all uniform look a little lean but not that bad but cylinders 13, 5, and 7 look different. And now with the Revelation that something is off with the valve train. That makes sense. Is this something I have to pull the head or can I get away with just pulling the valve cover and replacing the rocker? I mean the motor makes no noise. It did overheat on me last summer and I drove it after that with no noticeable impact to the truck. I put a cooler thermostat in it and flush the coolant and it was fine. I would think if I dropped the rocker it would have made noise? What has me really s******* bricks is the condition of all the hardware for the valve covers. It's all heavily rusted and rotted. I'm sure bolts are going to snap and I don't have a welder to simply tack on a washer and nut and spin them out

 

valve cover bolts are barely tight, use a good 6 point socket, i think they'll be find. Your plug gaps looks extremely large also I'm thinking .065" or more. Plugs spark different under compression then open air too. One reason inline testers work really while in isolating issues. With no tick or rattle 99% chance the valve train is fine, even an unseated valve seat would generate a tick I would think, but maybe the rocker tensioner will compensate that. the real question is what is your compression, regardless of what you see or hear, is it making 150+?

 

PAssanger side 150 even I stopped after cylinders 1&3 because the clearly audible sound of leak down and my gauge wouldn't hold pressure past 90
I bought the compression tester brand new from harbor freight. It's the Maddox brand. Never used it before and the little button to bleed off the pressure wouldn't stay seated now. Is that because the cylinder was leaking down and therefore there was no positive pressure holding the bleed er button closed or just a **** gauge idk now my head's spinning. It's dark. It's cold. I've been out there all day This is my daily driver. I just dropped six grand into it and not sure really where to go here. Past pulling the valve cover and seeing What fun is in store for me next!
Gaps were between.40-.45 ngk platinums

 

If you had a dropped valve seat, or thrown rocker, you would have a consistent miss, not intermittent. The RED color on the plugs is likely due to the seafoam. (additives will do that.) They all look pretty much the same color to me, but, the pics aren't real big, and my eyes ain't the best. The fat gap though, that IS an issue. I would be real tempted to replace those with some good copper plugs, brand of your choice, properly gapped, and see if the problems go away.

 

Yeah but that sounds great. But my question is why wouldn't cylinders 1 and 3 behave the same as the cylinders on the opposite side during the compression test. When I move the gauge from cylinder one to cylinder to three Iland test i could easily hear the air moving and watch pressure bleeding off doesn't that indicate an issue with the valve train ?

 

Also those plugs that I bought were the same plugs that were in the truck when I got it. Not saying that's necessarily a good thing but those were the plugs that they recommended and they happen to be the same exact plugs that way in the truck when I got it which were also done within the year prior to me buying the truck I'm not going to lie. I would love nothing more than to not have to go any further. My life is being destroyed by this truck. It's siphoned off my savings and kept me out of work for the last month because I live an hour from anything. So if you're telling me I can avoid all that that would be fantastic. I'm just trying to understand

 

Is the cylinder bleeding off pressure, or is your gauge? Cylinders don't seal perfectly, neither do valves. So long as your compression numbers are all north of 100PSI, and within around 15% of each other, it's all good. Consider that even at idle, the cylinder only needs to contain that pressure for milliseconds.....

 

Cylinders one and 3 were going up to 90 lb even but again my gauge was losing pressure and I was hearing pressure bleed off as I was testing

 

A compression tester should technically hold the peak pressure it reads indefinitely , if the needle is dropping the gauge isn't sealing correctly, and could be your hissing, also helps to oil threads and oring to make sure you have a good seal in the spark plug hole and be able to remove the tester again

 

I could the hear the pressure bleeding off in the valve cover like 100% no mistaking where it was coming from. The gauge was losing pressure and I could pinpoint where that was at the button but I can also hear the pressure working its way through the top of the head at the same time
I put the new plugs on the passenger side where everything seemed fine. No plugs in the driver side yet. I'm going to go back out tomorrow and give it a go. When I was testing the side that was reading 150 it had to step up to that pressure. It didn't just go there on the first revolution. Had to crank a couple times. I'm assuming it's going to be the same thing for that side and in between the revolutions and the engine turning over I could hear the pressure bleeding off just to be clear cuz I appreciate the information you're giving me right now
I'm assuming that valve is open but should it close as the engines turning over if everything is ok with valve train ?