Odd spark plug fouling

[1980sel]

So i have been playing with the CO adjustment lately....I had it too rich but before I readjusted I did a complete tune up..here's the part that's confusing me...all the plugs on the pass side were carbon fouled evenly and all the ones on the driver side were clean...I've since readjusted and i think i got it pretty dead on...also got it emissioned tested and the results showed good numbers...I've checked the plugs on the passenger side and they are clean after about 20 miles mixed driving..I just don't understand why half were fouled...

[TJ 450]

That seems odd, but I have had a similar experience playing with the idle CO adjustment. I can only imagine that the fuel dist has caused it somehow.

Tim

[1980sel]

I'm sure it did being adjusted too rich I just expected both sides to be even...it is reassuring to know you had a similar experiance though.