Help!
My C230 has 85000 miles. I am the original owner. About a month ago, i was in stop and go traffic for three hours. The next day, after the car warmed up , it felt like it was misfiring. I drove it for about an hour, and the check engine light came on. I figured I was due for a tune up and did it myself with the help of the forum. The car still misfired and the car had error code for misfires on 1,2 & 3 along with upstream O2 sensor. I relplaced the fuel filter. I then replaced the sensor and it still runs poorly. I did a compression test and #1 was 140, and 2, 3 & 4 were at 160. I did a wet test on #1 and it was still 140. Since I have been running regular gas in the car, I thought that there was carbon build up in the cylinders. I used a marine product called "power tune" to clean out the cylinders. I sprayed the stuff into the air intake with the car running. I then sprayed this stuff directly into each cylinder. The car still misses and the codes alway start with misfire in cylinder #1. It then goes to 3, then 2 and eventully 4. I tried switching coils 1 and 4 with no change. The spark plugs (original) looked like they were wearing normally.
Any sugestions are welcome. (I already agreed to use only high test gas).

Thanks
Tom