Manifold, EGR valve body, and pipes are all made of aluminum. Any machine shop can TIG broken parts back together, for a LOT cheaper than replacing them. But yes, you'll have to remove the parts and take them to the machine shop. Even paying the mechanic to remove the parts, paying the machine shop to TIG them, and paying the mechanic again to re-install them is going to be cheaper than buying new MB parts.

You can also try ebay.de for buying used parts. Many of the German sellers do speak English, and will ship to the US if you ask. While these om606 turbo engines are somewhat rare in the US, they are commonplace in europe. I recently bought an om606 turbo intake manifold from ebay.de for $40 + $60 shipping = $100 and it even came with the MAF still bolted on.

The MAF CEL when driving through dusty places is concerning though. That's what your air filter is for. The air filter box on these cars can become warped from the heat of the turbo, preventing a good seal on the filter. Check that yours isn't warped. You should be able to drive through a Iraq desert sand storm without getting a MAF CEL. I'm certain you have a leak somewhere, allowing unfiltered air to enter.

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1998 E300 turbodiesel

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