I am interested in buying a 300e. I test drove a 1991 with 144k mi. on it yesterday. Using a previous post I found I made sure to check some common problems. It has two on the list.

The first is oil leaking from the head gasket. It has no oil in the water and doesn't burn oil, so I think that is probably just a minor leak and I think I can elect to deal with it or not. Apparently this costs about $1000 to replace at a shop, but I've done head gaskets before.

My biggest concern is a lumpy idle. It seemed to rev fine and had good power, but it was definately missing a beat at idle. This did not change at all when the engine warmed up. It wasn't hunting for idle like what I'm used to with a bad oxygen sensor, more like a cylinder not firing, but I am not familiar with MB EFI, so I can rule nothing out. Since this was listed as a thing to check for on the used 300e checklist, I'm concerned. Does it mean that it is common or that it is an expensive fix or both???

Thank for your help.
This is a very cool and helpful forum.
Brian Harper
brian@anntec.com

the oil leak may NOT be a head gasket leak, specially if it is at the front cover seal area, which is very common. You can treat as the head gasket for price negotiation if you are really interested in the car.
However, the lumpy idle may be something as simple as a vacuum leak or it may be related to the head gasket.
Any records on the car? last service maintenance?
Records on these cars are very important, specially on older cars since repairs can become expensive real quick!

__________________
J.H.
'86 300E

I have owned 300Es with both the 103 and the 104 motors and they both developed idle problems. It can be both frustrating and very expensive to fix as not even authorised service centres seem able to pin the problem down; they just keep changing components hoping they will eventually fix it. Personally I would walk away and keep looking; at least start off with a car that is running properly.
Have a nice day
BriNZ

I have owned 300Es with both the 103 and the 104 motors and they both developed idle problems. It can be both frustrating and very expensive to fix as not even authorised service centres seem able to pin the problem down; they just keep changing components hoping they will eventually fix it. Personally I would walk away and keep looking; at least start off with a car that is running properly.
Have a nice day
BriNZ