Hey fellas. I have a 2000 ml320 with 56,000 miles. The check engine light came on a few months ago but I didn't have a chance to get the truck checked, just figured it was an oxgen sensor. But thank god for this site, just found it today.Transmission started slipping inconsistently about a month ago and now it slips constantly and usually gets stuck in 3rd gear. When I took it to auto zone and had it hooked up to the tester i got 3 codes back (P0170,P0173,P0700). Judging from the input at this site I figure that the P0170 and P0173 are related to the MAF. But what scares me is the P0700 code which the auto zone guy said meant Transmission Control System Malfunction. Has anyone ever had this experience and if so can you share your input or advice. Much appreciated.