Do not buy one on ebay....this is one of many parts than can look brand new but be DOA. Lots of complaints. Go to Autozone and have them read the fault codes and reset the CEL (free). They will probably tell you O2 sensors but don't be too quick to buy FOUR.

I paid $240 on-line for my MAF for an ML430. This is at MOST a 5 minute job to replace and you only need a screwdriver. It will take you longer to clean up than it will to install the part.

I believe my fault codes were P0173 and P0170. Get new MAF, install it, have autozone reset the CEL and the engine computer will take it from there.

I did my repair 12 months/14,000 miles ago....no problems with CEL since then.

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Jim