AI Damage1998 Mitsubishi Diamante: common problems
Owners of the 1998 Mitsubishi Diamante filed 27 complaints with NHTSA, most often about visibility and service brakes. Details by component below, with sources.
Key figures
- Owner complaints
- 27
- involving a crash
- 1
What fails most often
- 1 Visibility 59% of all complaints
- 2 Service brakes 11% of all complaints
- 3 Vehicle speed control 11% of all complaints
- 4 Electrical system 7% of all complaints
- 5 Engine and cooling 4% of all complaints
- 6 Equipment 4% of all complaints
- 7 Seat belts 4% of all complaints
- 8 Steering 4% of all complaints
- Visibility: 16 complaints (59% of all).
- Service brakes: 3 complaints (11% of all).
- Vehicle speed control: 3 complaints (11% of all), 1 of them with a crash reported by the owner.
- Electrical system: 2 complaints (7% of all).
- Engine and cooling: 1 complaints (4% of all).
Engines and transmissions
US-market versions per EPA. On the right: how many NHTSA complaints name this engine or transmission type.
- 3.5 L · petrol · 6 cyl
- automatic, 4-speed
Drive: FWD
Symptoms owners describe
How many of the 27 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) |
|---|---|---|---|
| Visibility | 16 | 0 | 0 |
| Service brakes | 3 | 0 | 0 |
| Vehicle speed control | 3 | 1 | 0 |
| Electrical system | 2 | 0 | 0 |
| Engine and cooling | 1 | 0 | 0 |
| Equipment | 1 | 0 | 0 |
| Seat belts | 1 | 0 | 0 |
| Steering | 1 | 0 | 0 |
| Structure | 1 | 0 | 0 |
| Tires | 1 | 0 | 0 |
| Wheels | 1 | 0 | 0 |
| Other | 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.
This is the second time since december 2003 that the accelerator stuck while in reverse and the brakes failed, causing property damage and injuries. This is very dangerous and I thank god that no little kids were killed!!! The first time it happened I called mitsubishi and reported the problem and never got a response.
The heater core has failed (once again) I am not sure of any company that has realeased their cars with such a major failure without taking some kind of responsibility to recall this item in the car. Nearly all of the heater cores from mitsubishi diamantes that I have seen are all bad.
We just cleared canadian customs at blaine wa, pacific crossing, and were accelerating to speed limit on I 5 freeway when the car accelerated to near 100 miles an hour. The tach at some point was 7500 and increasing.
This is the second time the heater core has started to leak. It was replaced 40k miles ago and I was charged $ 1,000 for repair costs. Having researched this, it is due to faulty heater core gaskets which mitsubishi replaced the defective gaskets with a redesigned one.
Will not pass emission there are no readiness codes stored in computer.
Everytime the heater is switched on, I can feel a weird smell which will last for about 10 mins. This smell seems like suffocating and have to open the windows for the fresh air to enter. There is some kind of leak in the engine compartment, I am not sure where the leak is from. I am bit worried abt the smell. Thanks
This caused child to be locked in the seat belt and unable to move. Seat belt had to be cut near the waistline area to free the child.
Consumer also states that cd player is inoperative, no radio code stored, armrest compartment hook lock broken, power steering fluid on minimum level.
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 7,189 of 36,656 model years in the NHTSA data (top 20% most complained about).
On average one model year of the Diamante has 42 complaints (12 years in the data). This year has 27, below average.
What to check before buying
- Visibility. Wipers, mirrors, defrosters, cracked glass.
- Service brakes. Pedal feel, ABS operation, leaks, discs and hoses.
- Vehicle speed control. Accelerator pedal, cruise control, throttle codes.
- Electrical system. Scan all modules, test the battery and alternator, inspect connectors near the impact zone.
Other years of this model
Questions and answers
What are the most common problems with the 1998 Mitsubishi Diamante?
Owner complaints to NHTSA most often mention: visibility, service brakes, vehicle speed control. Total complaints: 27. The most frequent symptoms in complaint texts: A/C or heater (56%), windows, sunroof (15%), overheating, coolant loss (7%).
How many service bulletins (TSB) were issued for the 1998 Mitsubishi Diamante?
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 1998 Mitsubishi Diamante 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 1998 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 2026-11-05.