1995 C280 Engine Miss & Steering Vibration
 

My wife's 1995 C280 with 72,000 miles has developed two problems as follows:

1. When driving at highway speed (65 mph) the engine sometimes develops a miss in one cylinder. The computer must detect this miss and, I believe, must shut down the fuel injector to this cylinder since when you stop the engine and restart it everything is ok. Also, when started cold and only driven for a short distance and restarted, it also has a "miss" for 10-15 seconds. This weekend it tripped the check engine light and I guess I will need to take it to MB to have it checked out. At 69,000 miles the check engine light came on and the computer indicated a "miss" and also a bad temperature sensor. The temp sensor was replaced along with the air mass sensor which the mechanic indicated was getting "sluggish." Evidently, there is also something else that needs attention. Any thoughts?

2. At speeds of 68 mph and above, there is a vibration that is felt in the steering wheel. Thought this might be wheel inbalance so I had the wheels rebalanced (which were not that far out of balance it turned out) but still have the vibration. I have heard there is a shock absorber on the steering column and was wondering if this could be causing the problem? The car had an alignment at 60,000 miles. Any other parts that would cause this problem at this mileage/age?

Check the wiring harness, coils and resistor tips. After y7ou check codes.

If the wheels are straight, tires are well balanced, rotation has no effect on it and the front end is solid, replace the steering shock/damper.


Joe

1995 C280 has a couple issues that could cause poor running/mis-firing. One is the degradation of the main wiring harness in the engine bay. The other is a faulty Over-Voltage Protection (OVP) relay.

Have both these checked.

Also, the above post is correct. Check electrical ignition components...

For your vibration? Tires, wheel balance, steering components, suspension components, driveshaft parts, etc. Big list of things...

I had similar problems in regards to the roughness that was corrected by restarting the engine.

Firstly, when the engine computer discover's a mis-fire within a cylinder, it shuts down fuel to that particular cylinder to protect the catatlytic converter from having raw fuel pass through it.

This happened to my engine at about 110,000 miles. The problem was corrected with:

1) New (OEM) Bosch spark plugs
2) New plug wires
3) New coil ends/boots (cheap).

Good luck!

Well, after the techs at Mercedes finished diagnosing the problems the following is what they found.

Engine miss was caused by a deteriorated main engine wiring harness (ouch! -- the cost of this part is $636 and $575 in labor to install). Appealed to Mercedes for a "Goodwill" warranty repair and Mercedes agreed to cover half of part and labor. As has been discussed on this forum, this is one of the weak points of 94-96 C-Class and E-Class vehicles where wire insulation drys out, cracks and breaks off. In my case wire insulation was cracked and was holding moisture causing occasional engine miss and check engine light to come on.

Steering vibration was caused by a broken belt in the drivers side rear tire along with out-of-round tires in front. New tires all-around together with 4-wheel alignment solved this problem. Also steering damper was becoming weak and leaking oil so refreshed this item also.

Thanks everyone for your comments!

Next time bring it too me, even with the 50% goodwill I beleive I could have beaten that price.



Joe
Behind The Star Inc.
Raleigh NC