AI Damage1986 Mercedes-Benz 420: common problems
Owners of the 1986 Mercedes-Benz 420 filed 6 complaints with NHTSA, most often about vehicle speed control and equipment. Details by component below, with sources.
Key figures
- Owner complaints
- 6
- involving a crash
- 2
What fails most often
- 1 Vehicle speed control 33% of all complaints
- 2 Equipment 17% of all complaints
- 3 Exterior lighting 17% of all complaints
- 4 Fuel system 17% of all complaints
- 5 Structure 17% of all complaints
- 6 Suspension 17% of all complaints
- 7 Tires 17% of all complaints
- Vehicle speed control: 2 complaints (33% of all), 2 of them with a crash reported by the owner.
- Equipment: 1 complaints (17% of all).
- Exterior lighting: 1 complaints (17% of all).
- Fuel system: 1 complaints (17% of all).
- Structure: 1 complaints (17% of all).
Engines and transmissions
US-market versions per EPA. On the right: how many NHTSA complaints name this engine or transmission type.
- 4.2 L · petrol · 8 cyl
- automatic, 4-speed
Drive: RWD
Symptoms owners describe
How many of the 6 NHTSA complaints mention each symptom (automatic count from complaint text; one complaint can mention several).
Components owners complain about
| Component | Owner complaints | involving a crash | Technical service bulletins (TSB) |
|---|---|---|---|
| Vehicle speed control | 2 | 2 | 0 |
| Equipment | 1 | 0 | 0 |
| Exterior lighting | 1 | 0 | 0 |
| Fuel system | 1 | 0 | 0 |
| Structure | 1 | 0 | 0 |
| Suspension | 1 | 0 | 0 |
| Tires | 1 | 0 | 0 |
What owners report
Short excerpts of NHTSA complaints in the original wording. These are owner statements not verified by NHTSA; personal data removed.
Got in the vehicle, started the ignition, and vehicle accelerated during 80 mph on wet pavement. Vehicle kept spinning around and around and slammed against the curb and bounced back and forth against the curb. Also, wheel came off and vehicle ended up in consumer's yard between an oak tree and a telephone pole.
The car accelerated when trying to stop at a light. Please describe. Tt
Mechanic was going to service engine when he pushed hood off. Hood flew off and broke windshield, and chipped the paint. Hinge spring was detached from right side of hood. Dealership was aware of problem.
Bridgestone tires (p205 65 r15) experienced tread separation, consumer is requesting reimbursement for the replacement of the faulty tires.
The consumer state's when driving their is a gasoline smell within the vehicle, the antenna is broken, brake lightand the tail light failed and their is a hole within the gas tank. Mjs
Right rear lower control arm rusted through. No other subframe corrosion visible.
When owners complained
NHTSA complaints by filing year. The peak shows at what age the problems show up most.
Comparison
By complaint count this model year ranks 13,281 of 36,659 model years in the NHTSA data (top 36% most complained about).
On average one model year of the 420 has 7 complaints (12 years in the data). This year has 6, about average.
What to check before buying
- Vehicle speed control. Accelerator pedal, cruise control, throttle codes.
- Exterior lighting. Headlamps, leveling, sensors and mounts after a frontal hit.
- Fuel system. Fuel smell, leaks, rough running, fuel-system codes.
- Structure. Rails, pillars, panel gaps, signs of pulling or welding.
Other years of this model
Questions and answers
What are the most common problems with the 1986 Mercedes-Benz 420?
Owner complaints to NHTSA most often mention: vehicle speed control, equipment, exterior lighting. Total complaints: 6. The most frequent symptoms in complaint texts: headlights and tail lights (17%), rust, corrosion (17%).
How many service bulletins (TSB) were issued for the 1986 Mercedes-Benz 420?
NHTSA lists 0 manufacturer service bulletins for this year. A bulletin tells dealers how to diagnose or fix a known issue; it is not a recall.
Should I buy a 1986 Mercedes-Benz 420 from a US auction?
Owner complaints describe defects, not crash damage. Before bidding, check the components listed above and review the lot photos: VinWind builds a report of visible and hidden damage by VIN.
Other 1986 models
Read also
Sources: public NHTSA data (USA): service bulletins and owner complaints; YouTube: links to videos credited to their authors. Complaints are owner statements not verified by NHTSA, and describe defects rather than crash damage. Data updated 2026-11-06.