GWhat1

Hers's the short version. Just had EGR valve and tubing plus the CPS sensor replaced on my 2000 ML320. The car was shuttting itself off when coming to a stop. No shuddering or running rough. There was no CEL on but a scan showed the bad EGR. They found the CPS while driving with the scan tool and it shut off. It didn't throw a code of any kind. EGR replaced on Wednesday of last week and CPS on thurs. The car was running smoth when I took it in. no miss of any kind. Friday am CEL comes on. Cylinder 6 misfire. Took it immediately by shop,they reset and said probably a fluke. Couldn't have anything to do with the work they had done. It ran smooth until today. CEL came on again and car started running rough. It ran rough with CEl on for about 10 miles then all of a sudden light went off and engine smoothed out. Of course this happened when shop was closed. I feel like its the cps but am not a mechanic and know just enough to be dangerous. Any help would be appreciated.

GWhat1

Anyone? please...