Sudden increase in noise - PeachParts Mercedes-Benz Forum

JayK · #1 03-12-2012, 12:15 PM

I was just driving up a bridge when my 1995 E300d started sounding like the semi's diving next to me. Oil pressure is fine, and it's shifting fine also. So my suspicion is the injection pump, but not sure. It was rebuilt by a reputable shop about 2 years ago. The noise is normal the "grinding walnuts" it always does, but MUCH louder. Also a little black smoke.

I happen to be parked close to Helms Brothers Mercedes in Queens, but want to take it to Gene's another 20 minutes away. Should I? I don't have any of my regular tools to I can't get a good look at anything.

Orv · #2 03-12-2012, 01:28 PM

If it was accompanied by a noticeable increase in vibration, probably engine mounts.

JayK · #3 03-13-2012, 07:49 AM

I made it genes fine, but had to stay on the highway to avoid running too hot. The mounts are new. Gene thinks its running rich, but can't get to it for a week. I need to drive the car, and any troubleshooting help would be great. The funny thing is that when I started it this morning it sounded fine for about 10 seconds, then got loud and smoky again. My gut tells me that means the injection pump is not out of alignment. For some reason I suspect something vacuum controlled, but I'm not sure why. This OM606 doesn't have much computer control as far as I know. Has anyone encountered this before?

TMAllison · #4 03-13-2012, 10:57 AM

Look for disconnected vacuum lines and fuel leaks (plastic fuel lines/delivery valves).

IP's usually outlast the engine; the exceptions to that are when folks start messing with them.

JayK · #5 04-23-2012, 09:49 AM

I forgot post a follow up. After doing what little troubleshooting I could do with my limited tools, I brought it to Gene's. Anyone who knows him will know why my car stayed there two weeks. But he fixed it. It can be difficult to communicate with Eugene sometimes, but I understand that some mechanism, perhaps a key, that aligns the cam with it's respective chain pulley sheared. He was able to get a new cam from another customer of his. Grand total P&L was $900. How does that all sound?

fdanielson · #6 01-06-2013, 09:48 AM

I had a similar experience driving home on vacation with 800 or so miles to go. The symptoms are almost exactly the same. It all of a sudden got louder and now sounds like a semi truck. Fuel milage is about the same, it runs a bit hotter, idles poorlly, stalls at idle, and smokes under idle and acceleration. Power does not seem to be diminished and it drives fine on the highway except for being loud.