Hello everyone, I am new to mercedes; I had recently purchased a 1990 190e 2.6 auto off of a friend of mine and it runs fine to get me from here to there. Although it is a higher end vehicle of the 1990s, it does have it's problems as I read other people have problems too. This is my daily driver between work and schhol and my time to work on it is limited so I want to do some research before taking anything apart to work on it. First of all, the windshield wiper doesnt work. I would test it but Mitchell doesn't have any wiring diagrams for this model and I would rather not use my power probe on something i shouldn't. Second, it doesn't seem to be very good on gas, maybe 150-200 miles a tank? My odometer doesn't work so i'm taking a guess. Also, i changed the plugs and wires ($250!!!!!) and ran them for a week... Today, zi removed one by one, and each of them are a beautiful shade of white. Now, the intake hose going to the front of the vehicle next to the left head light is broken and not connected to the air collector. Also, there is a vacuum line broken off directly below the valve cover vent (to air collector) that i assume travels toward the right strut tower. However, when i start it up, it smells pretty badly of gas. every time i uncap the fuel cap, it seems to be under great vacuum in the tank (clogged charcoal canister vent?) and when it hits a certain RPM (tach doesn't work), there is a bad rattling/rotational sound coming from either the front lower or very front of the engine compartment; like a very loose exhaust shield, but I'm leaning towards an accessory drive or fan (the fan appears to be screwed to the pulley with drywall screws! does not rotate by hand!) does anyone have any information they could pass on? I'm new here so cut me some slack!

 

Considering the delapidation of some other parts you've mentioned I think it's highly likely the fuel problem you're having is due to a badly leaking fuel distributor, which is basically the heart of the K-Jetronic type of fuel injection systems. They're a terrific system when maintained, race quality but being mechanical at its core the fuel distribution is sensitive to wear and age and these days many are leaky. Just pull off the air cleaner case and have a look at the fuel distributor head underneath, where all the injector piping runs out of and see if it's discoloured with leaking fuel.

You can find used replacement or off the shelf reconditioned head units for the fuel distributor but it isn't recommended. Anything but a qualified specialist on this type of system with good references are infamous for ongoing problems. I went to a race builder who specialises in Jetronic systems and now get fantastic economy and terrific performance out of mine, I can drive all day with the fuel guage hardly moving, it uses less than smaller fours I've had but while it was leaky it went through the juice. Probably those double fuel pumps, the injection on these is capable of feeding far more gas than needed, which is probably the Jetronic's racetrack heritage showing through.

On the plus side if you ever warm over the engine with a cam change and other enhancements you won't need to change the fuel system, you can get as much power as the engine can give with this one. But you want it in good working order.

Also worth checking the fuel pumps for leaking, these wear too.

The cold air intake for the air cleaner assembly just slots into place, with a retainer bolt at the front and a fitted hose at the back. If it's cracked or a piece is missing try some local auto wreckers. It does help because it gets pretty hot under the bonnet in traffic.

You definitely want to identify the location of that rattling sound. It could be a bearing noise. Exhaust shields can get rattly though, I wound up cutting part of mine off.

 

Hey odysean. Proud to have a 190e (1990). I also am dismantling a 1993 190e. Many parts will interchange. This wrecked MB had 134,000 when disabled by a LF collision. If interested, I might be able to provide serviceable used parts for you. Also, it has the gray leather interior which is in great condition, not even a tare on the drivers seat. Good luck with your MB. My Email is wapetty@comcast.net. -Wayne