I had the same code with my 96 SL, I had to replace the purge valve located in front of the ABS pump, it was about $96 with the MBCA discount at Park Place. I tried checking the purge system and all the lines, even replace the gas cap, but it turned out to be the valve. You can test them, they should make a fast clicking sound, if they don't, it is bad. Good luck!
Brian

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Brian W. Heitman

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