2024-11-16 -- Mercedes Benz R170

The R170 is indeed a classic car with a lot of potential. However, unlike newer cars, finding specific parts for older models can be challenging. I've made the decision to embark on a classic car restoration project, knowing that it will involve countless hours of internet research and visits to salvage yards.

I purchased a low-mileage R170 at an auction in Florida and had it shipped across the country to California.

The car had been driven less than 1,000 miles per year (1600km/yr) and appeared to be in good condition, with minimal rust and no major damage.

The car was originally purchased by an author who worked closely with Mercedes-Benz USA to write an article for a local magazine. The car came with a collection of floppy disks, CDs, slides, large-format photographs, and sales and marketing training materials, along with the published article itself.

Sadly, the original owner's husband passed away shortly after purchasing the car. Eventually she entered hospice care and passed away. The car remained in a garage for over 15 years following her death.

When the car arrived, I was pleasantly surprised by its quality. It exceeded my expectations.

The job entailed a comprehensive inventory of the vehicle, a road test to assess its operational capabilities, and an identification of any necessary remedial actions.

While I aimed to preserve the car's original state, I decided on upgrades like improved lighting, a rearview camera, and Android Auto compatibility.

But first I had to register the car in California.

Next task involved replacing all fluids, filters, and spark plugs. The car's maximum speed was limited to approximately 60 mph. This included replacing the engine oil and filter, transmission fluid and filter, differential fluid and brake flush.

Replacing the transmission and differential fluid required a specialized lift, so I took the car to an independent Mercedes shop for that service. The shop manager offered to replace all belts at no additional labor cost, and I accepted the offer.

I was able to replace the spark plugs, radiator fluid, and thermostat myself at home, after I purchased the parts from Mercedes dealership.

The tires were over 20 years old and needed replacement. The rims had significant humidity damage, causing the clear coat to peel. Repairing the rims through powder coating would cost $800, which was more expensive than purchasing new rims, mounting them, and having them balanced before shipping.

Next, I removed all the chrome pieces. From this:

To this:

Many of the interior plastic parts, such as the door seals and trim, were deteriorating. I had to either purchase new parts or salvage them from junkyards to repair the damaged ones.

As you can see, all the plastic pieces are missing!

Door trims had a poor condition:

All the hard plastic parts had deteriorated and needed to be repainted. Many parts were broken and required repair to reattach the damaged pieces.

The reverse lights weren't working. The issue was with the shifter. I couldn't find a used replacement at a reasonable price, and a new one was very expensive.

Upgrading to LED lighting proved to be more complex than anticipated. While transitioning from high-resistance, high-amperage lights to low-resistance, low-amperage LEDs should have been straightforward, it caused confusion for the car's ECU, triggering numerous warning lights on the dashboard. After extensive experimentation with different brands, adding resistors, and modifying relays, I was able to stabilize the LED lighting system. I'm so accustomed to high-powered LEDs (and even laser lights in one of my cars) that traditional incandescent lights now seem dim in comparison.

I also replaced all the burned-out and working dashboard, cluster, console, interior (dome, glovebox, and door), trunk, and under-hood lights with LEDs. A surprising challenge was that smaller LEDs without logic boards have polarity.

Next, I had to address the power mirrors, which were stuck. Replacing the mirror motors resolved the issue.

I decided to tackle the broken mirror parts and a dent on the rear fender. This was my first attempt at bodywork.

The new head unit arrived, and I faced the complex task of integrating a digital electric system with an optical/electrical system. This involved many hours of work with various optical-to-electric and electric-to-optic transceivers. Eventually, I successfully connected the optical power amplifier and CD changer to the new head unit.

Another complex task involved routing the camera wires through the firewall, mounting the rear camera, and configuring it to activate automatically when shifting into reverse gear.

Unexpectedly, the car's cellular system and antenna interfered with the new head unit, creating a hissing noise. Ironically, engine noise did not cause any interference. While I disconnected the car's built-in cellular system, the antenna, integrated into the rear bumper, and its amplifier module remained connected to the ECU, contributing to the issue. 

It took many hours to separate over 40 cables, shield them, or add capacitors and inductors to create an effective noise filter.

Routing the cables through the wiring harness near the convertible roof mechanism was equally time-consuming. A significant challenge was the placement of the fuel tank directly behind the passenger cabin and in front of the trunk. Once in the trunk, the cable had to be carefully routed through the metal braces of the trunk door to reach the center rear position. This central placement would simplify future camera calibration.

Just when I thought the project was nearing completion, the A/C stopped working. I discovered a faulty fan as the culprit. An initial repair attempt was unsuccessful, as the fan failed again after a week. The challenging location of the fan made the replacement particularly difficult for someone of my age.

Just as I was about to celebrate the project's completion, the engine light illuminated.

Back to diagnosing the issue and sourcing the necessary parts...

Fortunately, the issue was resolved by replacing a simple sensor. The problem wasn't with the camshaft itself, just the sensor. Although irrelevant errors were misleading me!

The process was the best on-the-job training I could've asked for. However, I had to sell the car due to the inconvenience of managing five cars in the garage and driveway, especially when this one was out of commission.

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(c) I personally took these photos and videos and own the rights to them. Please feel free to use them as you wish.