hi all,

I recently did a compression test on my 93 240 wagon.
I got 190 across the board.
this was done with the engine at full operating temp with the thermostat open.

So, according to what I have read, This would indicate that I have some pretty heavy
carbon buildup.

How would one go about removing the carbon?
I have read about using water to steam clean the engine while running
by feeding water to the intake via a vacuum line.
I have also heard of pulling the head....

Has anybody dealt with is before? I'd really like to get out of pulling the head....
Is there some sort of cleaning solvent I can use by spraying it into the intake?

I guess the real question is why would it have so much carbon in the first place?
improper fuel mixture? I checked the O2 sensor with a multimeter; readings were
just what the book (haynes) said they should be. OB diag LED reads 1-1-1.

I haven't had the car that long and I don't really know its history.

Thanks for any info
-sean