The Mercedes-Benz S55 AMG. Just the name itself evokes a sense of power, luxury, and performance. For enthusiasts and connoisseurs of fine automobiles, the W220 generation S55 AMG represents a sweet spot – a blend of classic Mercedes-Benz elegance with the raw, untamed power of AMG engineering. Recently, we had the opportunity to examine a W220 S55 AMG, and our initial inspection revealed a vehicle brimming with potential and a few intriguing mysteries.
This particular S55 AMG has been out of regular use for a period, though sheltered from the elements. A preliminary drive showcased the inherent smoothness and refined driving dynamics that are hallmarks of the S-Class lineage, even in a performance-oriented AMG variant. The climate control system, both air conditioning and heating, functioned correctly, adding to the immediate impression of a well-maintained, albeit slightly dormant, machine. Most of the car’s features operated as expected, with a few exceptions, common to the W220 platform, that are generally considered minor and rectifiable.
One such issue was with the DVD-based navigation system, which failed to activate, suggesting a potential problem with media readability. Troubleshooting points towards a potentially dirty laser lens or weakened laser optics within the navigation processor. Interestingly, the navigation media itself was the original disc that came with the vehicle. A spare W211 navigation processor is readily available, offering a potential solution should further investigation point to a hardware issue. Adding to the list of minor electronic quirks, the Alpine 6-disc CD changer refused to release its magazine. Visual inspection through the changer door revealed a disc loaded in slot one, but the tray mechanism seemed unresponsive to ejection commands.
Further inspection revealed that the soft-close doors, initially functional, had ceased to operate. This symptom strongly suggests a potential issue with the Pneumatic System Equipment (PSE) pump, possibly a blown fuse, a common occurrence and relatively simple fix in many W220 models. Addressing these minor electrical gremlins is part of the charm of owning and maintaining a vehicle of this caliber, preserving its original equipment and functionality. There’s a distinct satisfaction in bringing these systems back to their factory-intended glory, far more rewarding than resorting to aftermarket replacements, such as swapping the head unit for a more modern, albeit less integrated, system. Even the existing display, with a minor gray area, is preferable to replace with an OEM unit rather than a complete system overhaul. The simultaneous failure of the door locks and soft-close system reinforces the likelihood of a PSE-related issue, prompting an initial check of the relevant fuse and a subsequent investigation for potential pneumatic leaks within the system.
Delving deeper into the vehicle’s history, the previous owner disclosed purchasing the car with a pre-existing issue in the instrument cluster. The odometer displayed “——,” and the vehicle’s option configuration was unknown, masking features like DISTRONIC. This cluster malfunction also impacted the telematics system, incorrectly coded to D2B instead of MOST, rendering the TEL, NAV, and AUDIO displays blank, as if the systems were uninitialized. The seller was informed that the cluster “just needed programming,” a seemingly simple fix suggested by a dealer or someone with similar diagnostic capabilities. However, the persistence of the issue suggests that local dealerships may have deemed it beyond their scope or offered costly replacement as the only solution. Likely, attempts to resolve the “programming” issue proved more complex than initially anticipated, leading to its prolonged state of malfunction. Through proper diagnostic procedures and coding, the instrument cluster was successfully integrated into the Drive Authorization System. This action rectified the odometer display, pulling the correct mileage data directly from the Electronic Ignition Switch (EIS), as expected. Furthermore, the telematics coding was corrected to MOST, DISTRONIC and Dynamic Seats were correctly set to “Present,” restoring full functionality to all relevant menus and displays within the instrument cluster.
The presence of DISTRONIC in this S55 AMG was initially unexpected, especially considering prior experience with a W221 S600, where DISTRONIC PLUS was standard. The discovery of distance control buttons near the shifter and the absence of the protective grille cover piqued curiosity. A subsequent CarFax report revealed a past collision with a deer, likely explaining the grille damage and hinting at potential front-end repairs.
Another anomaly observed was the use of identical tire sizes on all four wheels. While technically incorrect for the W220 S55 AMG, this configuration surprisingly did not translate into noticeable traction issues. Even with 245-section tires all around, the car exhibited impressive grip. This unexpected performance characteristic, coupled with the vehicle’s robust acceleration, raised suspicions of a possible ECU tune. However, to respect the current owner’s preferences and avoid any unauthorized modifications, the ECU has not been interrogated to confirm or deny this suspicion. Visually, the car presents no obvious external modifications. However, a closer inspection underneath the vehicle could reveal potential aftermarket upgrades to the exhaust system or rear differential. The possibility of a Limited-Slip Differential (LSD) also lingers, given the car’s exceptional traction. Unlike systems that rely heavily on Electronic Stability Program (ESP) to mitigate wheelspin by braking individual wheels, this S55 AMG delivers power to the pavement with remarkable efficiency, exhibiting characteristics often associated with an LSD. In comparison, a W221 S600, when pushed from a rolling start, will frequently trigger the ESP warning light as the turbochargers engage, managing wheelspin. The more immediate power delivery of the supercharged AMG V8 Kompressor in the S55 AMG further contributes to this feeling of readily available traction. Diagnostic data obtained via DAS (Diagnostic Assistance System) revealed that the supercharger clutch remained engaged at all times during testing. This further fuels speculation about a possible fixed supercharger pulley modification, a common performance upgrade for these engines. Having driven a CLS55 AMG with a fixed pulley, the typical wheelspin issues associated with such a modification, especially during low-speed turns, are notably absent in this S55 AMG, adding another layer of intrigue to its performance characteristics.
Exterior examination suggests that the rear panels and doors retain their original paintwork. Subtle inconsistencies in emblem placement often betray panel refinishing, but in this case, the model designation emblems appear correctly positioned and spaced. Conversely, the hood and front fenders likely underwent refinishing following the deer collision, yet the “V8 Kompressor” lettering appears original or meticulously reapplied, demonstrating attention to detail in any prior repairs. Minor discrepancies in the hood-to-fender gaps are present but minimal and easily adjustable. A minor inconvenience is a slight misalignment in the hood release mechanism. The interior release lever fails to fully disengage the passenger-side latch without manual assistance from outside, suggesting a minor mechanical adjustment is needed rather than lubrication. However, given the vehicle is not currently under ownership, a more thorough investigation into this minor issue has been deferred.
In conclusion, this S55 AMG Mercedes-Benz presents itself as a compelling example of its breed. Despite minor electronic and cosmetic imperfections, and a history that includes a front-end collision, its core mechanicals and potent AMG powertrain appear robust and full of character. The unanswered questions surrounding potential performance modifications only add to its allure, making it a potentially exciting project for someone seeking a blend of classic Mercedes luxury, exhilarating AMG performance, and a touch of automotive mystery.
