W202 Complex Problems

[LostKiwi]

Looking at that connector you look to have the disintegrating wiring loom problem common on 1993-95 cars.
Mercedes changed the wiring harness insulation to a biodegradable plastic but unfortunately used a plastic that biodegrades whilst still in use, some cars having issues within a few years.
Top engine looms are very prone to it due to heat. My r129 had the issue and I had the engine and throttle body loom replaced to fix it.
The symptoms are random issues that slowly get worse and cracked insulation wherever it's visible such as at plug ends (as in your photo).

 

[mattkh]

Very happy for you.
Q1. What did the mechanic do to the MAP sensor.?
Q2. If the engine has been running and you stop the engine, then immediately start again, does the engine fire up straight away or carnk long.??

 

[Benzica]

Looking at that connector you look to have the disintegrating wiring loom problem common on 1993-95 cars.

I can believe it. Some wiring looked redone when I bought the car. Also the horn didn't work at the time because of a dead wire.

Very happy for you.
Q1. What did the mechanic do to the MAP sensor.?

Thank you. There is nothing on the bill about the MAP sensor and he didn't discuss it, but I imagine he had a look at least while doing diagnostics.

Q2. If the engine has been running and you stop the engine, then immediately start again, does the engine fire up straight away or carnk long.??

No change. It takes as long as usual. Furthermore, a couple of days after this work was finished, the crank's sound slowed down which I find a bit worrying. Perhaps it was too fast before and this is a good thing. I keep listening to YouTube videos of people starting up their C180s, but I can't come to a conclusion.

 

[mattkh]

, the crank's sound slowed down which I find a bit worrying

It seems to me that the battery is dying.
Please check that the alternator is outputting 14v.

 

[Benzica]

It seems to me that the battery is dying.
Please check that the alternator is outputting 14v.

You were right. A few days after your post, my car was dead on the driveway. It's okay now after a new battery. The car occasionally cuts out when stopping or slowing down, but is still driving much better.

 

[mattkh]

You were right. A few days after your post, my car was dead on the driveway. It's okay now after a new battery. The car occasionally cuts out when stopping or slowing down, but is still driving much better.

Very happy for you.