SO I get my "new" '96 C220 on the road after the mechanic fixed the fuel pump relay. This was the first time I got it on the road...MAN is this thing smooth!!! I am absolutely in love with it..and MB!!
While driving, I noticed the fuel gauge seems to have a short or bad electrical connection since while driving, it drops to "0" and after a while, jumps back up. No other gauges are acting up.
I noticed when the car first broke down (cranked but wouldn't start) the fuel gauge was "dead"..even after a fill up.
Could the mechanic have not secured the relay connections well? I know it could be a loose wire anywhere in the circuit, but I was wondering if there were other systems connected to the fuel gauge that I should be aware of when I start checking.
Slowly, but surely, I am learning about this great car.

Also, while I was at the parts store (new wiper blade), a passerby was telling me that he had one and they are extremely hard to maintain. He told me that MB electronics hate humidity and I should place those dehumidifying packets under the dash and other places. He also said tuneups averaged $400 and at 100K miles, a lot of the fuses will give out. He was aslo telling me that the car should be kept in a garage with a dehumidifier, since otherwise a lot of problems will arise down the road. This kind of alarmed me since I am on the Gulf Coast...the most humid area in the United States!! Not too sure how much to believe him about some stuff. I can see the fuses needing changing, but dehumidifying packets stuffed everywhere?

Fuel tank sending units are probably shot. Common on many MB models. If the problem only began after the repair, then something might not have been connested properly.

The M111 engined W202 from 1996- on a very reliable car. No wiring harness issues, no headgasket problems. Double row timing chain that is long lived. Reliable AC system.

The 16V four cylinder is tough and pretty much problem free. I know a few C220 owners with high mileage, and report few driveline issues.

The problems you might have include:

1. MAS (Mass Airflow Sensor) is an issue on many late model (OBDII) makes, including Mercedes. Thankfully, the MB MAS is a fraction of the cost of most others. (Our Mazda 626's unit is $1300, most MB's are about $300-500)

2. Fuel gauge sending units. Heard a rumour oxygenated fuels cause premature wear.

3. Evaporator temperature sensor. Can cause the AC to on the blink, but is a relatively inexpensive thing to fix.

4. Wiper might begin to hang up. Don't let the dealer sell you a $1200 new unit. It can be lubricated.

5. Fuel pump relay - this you already know.

6. Lower front ball joints wear out prior to 160,000 kilometers, often earlier. Worse if your roads are bad.

Change the oil and filter often and you'll keep the timing chain from premature wear and make all the other lubricated bits happy too. Change the tranny fluid and filter every 50,000 kilometers.

Ignore the fellow at the parts counter. But, it's not a Corolla either. These cars need care and attention. If you want a Maytag, shop elsewhere...

__________________
John Shellenberg
1998 C230 "Black Betty" 240K

http://img31.exs.cx/img31/4050/tophat6.gif

I had the same problem in my 96 c280 shortly after I purchased it. Having pulled fuel systems apart in the past and noticed lots of buildup on senders of cars that had sat for a while, I decided to try something on my car. I kept the tank full as much as possible. I would fill it with the best premium with Techron I could find and anytime I anticipated leaving it sit for more than a day I would fill it first right to the top. It worked. My fuel gauge no longer dips to zero. It would always do it at the same spot, roughly 60km into a full tank, so I was sure to keep it full above that. Apparently Shell fuels were bad for trashing senders and even after they said they had discontinued that additive they still continued to use it for some months after. There was a program just over a year ago to compensate people who could prove they had bought lots of Shell fuel and then required new senders. Try the full tank thing for a month or 2 and then see if you still need to spend money on parts.