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Warning: Long Post

To make a short story long...

I did a compression test on my car this weekend and got great numbers out of it for the dry test, and rather odd results for the wet test.

The good news is that all the cylinders are consistent
with pressures all within 5 psi of each other at about
200 psi when I did the dry compression test. Excellent numbers
IMO. The pressure rose smoothly with each stroke, etc. I gave the engine 5-6 strokes per cylinder.

I then dropped a few squirts of oil (a teaspoon or
two) in each cylinder for the wet test and got
consistent readings of 245-250 (!) in each cylinder.
Now I'm sure I didn't throw too much oil in there, and this doesn't sound like worn piston rings to me.

An inspection mirror through the plug hole revealed a
moderate amount of carbon and other crap build up in
the cylinders. I run Techron through the engine every 3K miles, so I was a bit surprised. But it does have 112K miles on it.

This engine burns NO oil whatsoever between oil
changes, so that implies that the rings are doing
their jobs. The buildup in the cylinders makes me
wonder... Would it be possible that the oil I squirted
in there got stuck on top of the piston and reduced
the volume of the cylinder enough to push up the
readings by 50psi?

While I was taking the plugs out I found that both the
plugs on the driver side and passenger side nearest
the firewall had flaky white powder all over the
connector (on the top where the coil supplies power to
the plug). I've never seen this before either. I
cleaned up all the plugs including these with ease and inspected the boots
and found no signs of corrosion of damage to any of them. I applied
some dielectric grease and anti-seize and popped them back in.

The engine has more power and runs smoother now with those 2 plugs
cleaned up. I highly doubt that they were doing their
job before. Funny thing is that those plugs (like the
others) had minimal and normal wear on the electrode
after 20K miles.
 
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