Perhaps I should add what has been done so far.:
new coil pack, cats, 4 o2 sensors, crank position sensor, temp sensor, belt, fluids and filters, magnecor wires, champion plugs, and...uhh...I think thats it. The truck has intermittent hassitation and seems to have a loss of power at all speeds, even idle. It will be fine, then poof, crap, almost dies from slow rpms, then poof, back to normal.

 

oh yeah, compression test is good..holding, and the vacume test fluctuated between 14 and 16....hence the valve question. Any ideas on the spark though?

 

Not real well verse on that model line but I do know from reading some bullitens to be careful before you condemn the engine. If memory serves check the flywheel and it's signal to the crankshaft position sensor. It could be a crack in the flywheel throwing off the signal, hence the extremely screwed up ignition timing which could make it "feel" like a valve problem or show like a valve problem.

which # are you getting compared to this

http://www.secondchancegarage.com/public/186.cfm

so we are on the same page as what the vacuum gauge is doing.

 

I am closest to 11 from that link. The engine is coils packes so I cant just twist a dizzy, I wish it were that easy. Also the juice going through the plug wires is screwy so I am thinking either ignition (ecu shot) or valve job. The flywheel cover isnt as easy as removing and inspecting. When I put the new crankshaft position sensor in I found that inspecting the flywheel will be a chore as well.

 

Someone with a ociliscope (sic) could cofirm but I'd think ignition/electrical before stuck vavle. If the crank signal is weak or corrupt it will send a false sig to the ecu and that retard ignition or just plain screw it up.

If you could get someone to scope the crank and cam sensors then you could confirm there operation. Also hooking a scanner up and looking at the data may help.

No CEL, no codes present correct?