1993 Nissan D21 V6 Engine Trouble

[barncat75]

170,000 mi, Automatic Transmission, 4wd

The problem is severe loss of power which can be partially remedied by disconnecting the crank position sensor. First noticed when towing, accompanied by truck running hot. Has gotten worse since and is so bad now that I can't get over the lip up onto the road when backing out of my driveway. Idles around 500rpm and is prone to stalling. When starting, will catch easily but if I let it stall, won't re-start. If I disconnect CPS, will start and run rough, can back out driveway but can't break 10mph up a hill. Have disconnected each spark plug wire and driven to see if maybe a cylinder was dead, figuring if I didn't notice a change in performance, the disconnected cylinder was dead. Each time engine still ran but with decreased power. I also did a compression gas test on the radiator and found no problems there. I noticed a vacuum line came off the fuel pressure regulator and was hopeful replacing it might help but no such luck. Plenty of smoke coming out tailpipe so I assume no plugged exhaust. Any ideas/suggestions?

Thanks,

[PapaSmurf2k3]

Have you checked your ignition timing?