I haven't done a compression test in over 15 years and I don't want to waste my time so here are a few questions.

1) warm engine or cold engine?

2) remove all spark plugs

3) disable ignition? pull plug at coil?

4) wide open throttle

5) disable EFI? where?

6) wet test on any bad cylinder - 1 tablespoon 30 weight

7) Does this stand true for our trucks? Compression readings for a gasoline engine should run around 125 to 175 psi. The compression should not vary over 15 to 20 psi from the highest to the lowest cylinder. Readings must be within 10 to 15 percent of each other. Correct?

 

warm it up, let cool enough to work on and to let the plugs cool
removing plugs makes it convenient if checking all cylinders
pull electric harness off coil, just pulling hivolt wire not good the spark will travel
throttle doesnt matter no plugs
efi do nothing
you dont want to do a wet test the heavier oil will only help seal the rings and build compression which makes it harder to find the bad cyl, dry test is the norm and is good
Anything under 100 should be looked at, some engines run around 110-150 with no real loss of power or oil burn.

 

If you haven't done a compression check in 15 years, why do you feel compelled to do one now?

 

Why not Jimmy?

 

I was just wondering what he thought might be wrong with it. You generally don't do a compression test for fun.

 

#8 plug is wet.

 

With oil?

 

#7 & #8 is the classic crossfire plug on our V8's. Wires routed correctly?

 

Wires are routed correctly. I went to disconnect the electrical harness at the coil, I'm sure it's the OEM, and that connection is super tight. I just spent the past 10 - 15 minutes trying to disconnect with no luck. Any tips on breaking it free?

 

10-15 minutes? According to the date on your last post, you be working on that puppy for 2 months!

You mean the Coil to Distributor wire or the POS connection terminal nut?