I have a 2002 ram 1500 SLT with 4.7 v-8 that has been running great and then yesterday when pulling out it revved up to 4000 rpm then slowly dropped until it died. The only CEL was for a #8 misfire. Cleared code and still won't run. When I started looking around the engine I discovered the lower radiator hose had blown off(the clamp was still tightened down and wouldn't go on until loosened). I also noticed that it sounds different when turning over, more labored sound. I checked fuel and pressure is fine and I smelled fuel when I removed plugs. I checked cylinder compression and only had 30 psi in all but #2, which was zero. Added oil and they all went up 30 psi more, including #2. Pulled valve covers and everything looks good, no obvious valve train issues, rotated engine and all opened and closed. I also rotated until the timings marks aligned and the alignment is good. No guides broken and chains are tight.
I have no idea what this good be. Is this head or head gasket issue or am I really looking at serious piston ring problem. It just seems odd that all would be so low, especially since it has been running very good, we have had no performance issues at all.

 

Won't really know how bad until you take it apart. Sounds like a head gasket. However if all cylinders increase 30psi with a shot of oil. Maybe time for a new motor. Not sure of your mileage.

 

Next step is a leak down test. The kit is cheap at a store like Harbor freight.