1998 Mitsubishi Diamante

Reliability, what owners report, and what it costs to keep.

69/100

Be careful

AVOIR's read: the numbers are mixed and the complaint record is worth reading before you commit.

What owners actually report

Owners have filed 27 complaints with NHTSA about the 1998 Mitsubishi Diamante, and it carries 1 recall. These are owner allegations rather than confirmed defects, but the pattern of what people complain about is the most useful signal a used buyer has.

Complaints by area, from NHTSA records for this model-year
Area	Complaints	Share
Visibility	14	52%
Vehicle speed control	3	11%
Service brakes	3	11%
Electrical system	2	7%
Visibility/wiper	1	4%
Engine and engine cooling	1	4%
Seat belts	1	4%
Steering	1	4%
Wheels	1	4%

In owners' own words

Verbatim from NHTSA complaint records, trimmed for length.

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 HE
NHTSA complaint: Visibility/wiper

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. T
NHTSA complaint: Vehicle speed control

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
NHTSA complaint: Visibility

WILL NOT PASS EMISSION THERE ARE NO READINESS CODES STORED IN COMPUTER. *TR
NHTSA complaint: Electrical system

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 TH
NHTSA complaint: Visibility

FAILURE OF HEATER CORE GASKETS RESULTING IN FUMES INSIDE THE CAR FROM ANTI-FREEZE; THIS IS THE 2ND TIME THIS HAS HAPPENED WITH THIS VEHICLE IN THE LAST 35,000 MILES AND THE REPAIR LABOR IS ESTIMATED AT 6 HOURS, WHICH IS
NHTSA complaint: Visibility

1998 MITSUBISHI DIAMANTE HEATER CORE LEAKING FOGGING WINDSHIELD DURING FREEWAY TRAVEL. HAZARD TO HEALTH WITH WHILE OPERATION AUTO. *NM
NHTSA complaint: Visibility

WHILE DRIVING CONSUMER SMELLED A BAD ODOR COMING FROM THE HEATER CORE. HEATER SYSTEM WAS LEAKING COOLANT. THIS HAPPENED THREE TIMES. THE SEAL HAD TO BE REPLACED. *AK THE VEHICLE'S HEATER CORE AND REFRIGERANT WERE REPL
NHTSA complaint: Visibility

Recalls on record

NHTSA lists 1 recall campaign for the 1998 Mitsubishi Diamante. Recalls are free to have fixed at a franchised dealer regardless of who owns the car now, but only if they were never done, so check the VIN of the specific car rather than trusting the model.

Equipment:other:labels 04V428000

CERTAIN PASSENGER VEHICLES FAIL TO CONFORM TO THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 208, 'OCCUPANT CRASH PROTECTION.' THE BILINGUAL ENGLISH/SPANISH REMOVABLE AIR BAG WARNING LABELS AFFIXED TO THE DASH AND TO THE SUNVISOR DO NOT MEET THE SIZE REQUIREMENTS OF THE STANDARD.

Risk: THIS DOES NOT MEET THE REQUIREMENTS OF THE STANDARD.

Fix: MITSUBISHI CARIBBEAN WILL MAIL A CUSTOMER NOTIFICATION LETTER CONTAINING A WRITTEN DESCRIPTION AND A GRAPHIC OF THE BI-LINGUAL DASHBOARD AIR BAG WARNING LABEL. IN ADDITION, ALL CURRENT 2000-2004 NATI

The seven scores

Reliability raw	85	excellent
Longevity est.	79	good
Maintenance	76	good
Depreciation	55	average
Performance	57	average
Efficiency	32	below average

How it compares in its class

Percentile ranks against other midsize & large cars in the catalog.

Reliability: better than 54% of midsize & large cars
Longevity: better than 63% of midsize & large cars
Running costs: better than 54% of midsize & large cars
Value retention: better than 30% of midsize & large cars

Which of these numbers are measured

What stands behind each score for this car:

Reliability 85: from NHTSA recalls and complaints. This one is a raw count: we do not have a sales figure for this model, so a high-volume car looks worse here than it should.
Longevity 79: an estimate from powertrain and brand record. No 200,000-mile population exists for a 1998 car yet, so this is a prior, not evidence.
Maintenance 76: repair-cost data where we have it for this model, otherwise a mechanical-complexity estimate from engine size, cylinder count and drivetrain.
Safety: no score. NHTSA crash testing thins out for older vehicles and we would rather show nothing than guess.

Common questions

What goes wrong with the 1998 Mitsubishi Diamante?

Owners have filed 27 complaints with NHTSA for this model-year, and visibility is the most reported area with 14 of them (52%). There is 1 recall on record. Check any specific car against its VIN before buying.

Is the 1998 Mitsubishi Diamante reliable?

AVOIR scores its reliability 85/100 (excellent) from NHTSA recall campaigns and complaint density. That figure is a raw complaint count, not yet adjusted for sales volume, so a high-volume model scores worse than it deserves.

How long will a 1998 Mitsubishi Diamante last?

AVOIR scores its longevity 79/100, but that figure is an estimate built from the powertrain and the brand's record, not a measurement. A 1998 car has no 200,000-mile population to observe yet, so treat it as a prior rather than evidence.

Should I buy a 1998 Mitsubishi Diamante?

AVOIR's read: be careful, because the numbers are mixed and the complaint record is worth reading before you commit. Its overall ownership score is 69/100. Condition, mileage and service history still matter more than any score, so get a pre-purchase inspection on the specific car.

Sources: NHTSA recalls and complaints, EPA fuel economy, IIHS awards, and live market listings. A score describes a model-year, not the individual car in front of you. Get a pre-purchase inspection.