Most common 2002 Mitsubishi Diamante problems
Share of the 123 complaints; one complaint can involve more than one system. "~" is the median mileage when the problem started.
Mitsubishi Diamante complaints by model year
Best Diamante years: 1995, 1999, 1998. Years to avoid: 2002, 2001, 2003, 2000. Compare all years →
2002 Mitsubishi Diamante recalls (3)
Equipment › Other › Labels
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.
Remedy: Mitsubishi caribbean will mail a customer notification letter containing a written description and a graphic of the bi-lingual dashboard air bag warning label.
Equipment › Other › Owners/service/other manual
Certain sport utility and passenger vehicles fail to comply with federal motor vehicle safety standard no. 225, "child restraint anchorage systems." the owner's manual does not contain a step-by-step description for headrest adjustment when installing a child restraint system (crs) tether strap.
Remedy: A letter outlining the problem will be sent to owners along with a sticker containing the correct instructions as well as instructions on where to affix the sticker in the owner's manual.
Electrical system › Wiring › Front underhood
On certain passenger vehicles, the main under hood electrical wiring harness May have insufficient clearance between the engine control harness and the exhaust heat shield. As a result, the harness could come in contact with the heat shield, which could result in melting of the harness insulation.
Remedy: Dealers will inspect the harness for damage and, if none is evident, will tie the harness back to prevent the harness from ever coming into contact with the heat shield.
What 2002 Mitsubishi Diamante owners say
A/C & heater all 69 →
'02 Mitsubishi Diamante; heater core failure; 2nd owner eff. 2/05; bought from same dealer that leased to 1 person; found many other owners suffering same issue on google to site: http://www.diamanteowners.com/forum/index.php?s=918c701e5465c87381ccae0aa22c20a3&showtopic=3615 I have been quoted $1200 by 2 dealers and $900 by a mechanic/independent. The dealer that leased the car to '1st owner' and sold it to me at end of lease told me that they are working on two diamantes per week for heater core replacement! Why is there no recall yet??? This leak - per brad/sale and service dealer states that if I fail to fix immediately - 10 hours of labor - radiator coolant will leak into passenger foot well/flood and the leakage goes over my computer that runs the car! 2 repairs a week is unacceptable!!! Please help!!! …
The first time my 5 year old son drove in this car, he vomitted. Everytime he rides in it he becomes nauseous. The car's windshield fogs up and a sickly sweet smell comes out of the vents. The windshield is covered in a permanent haze. We noticed these symptoms but had not given it a second thought since the car was new and had no reason to suspect major problems. The car was recently in the shop for 1 week, when we picked it up we really noticed the sweet smell and alerted the shop. After inspection the shop diagnozed it as a heater core problem, a leak that is vaporizing and condensating on the windshields. The anti-freeze fumes are noxious, and after some research we have found that Mitsubishi has been aware of the problem and has even issued 2 TSB about the problem. Mitsubishi fails to correct the problem by fixing the car. …
Engine & cooling all 38 →
Tl* the contact owns a 2002 Mitsubishi Diamante. The contact stated that while driving at 75 MPH, the contact attempted to brake but the brakes failed to respond without any warnings. The vehicle crashed into a passenger van. The vehicle was destroyed. The contact mentioned that two months prior to the failure the check engine light had illuminated. The vehicle was taken to an independent mechanic for diagnosis and was informed that the vehicle misfires, needed spark plugs, a fuel pump, a fuel injector, an EGR valve, and the engine surged erratically. The failure and current mileage was 140,000. Updated 12/06/12 updated 12/6/2012
This heater core leaks directly over computers which control the engine - and could cause it to act unpredictably or cut out altogether when driving. * anti-freeze contains ethylene gylcol which can cause serious respiratory damage * the leaking anti-freeze causes a film to form on the windshield, which can cause the windscreen to fog up suddenly, obscuring the view of the road and potentially causing a collision it will cost me more than 900.00 to repair this item, plus the cost to replace my carpet and to clean the interior of my vehicle. Plus I do not know if I will everget rid of the smell and this will most likely lower the resale value costing me even more in the long term.I would expect this kind of thing to happen to a car that is more than 10 years or old. …
Transmission & drivetrain
I was driving my Mitsubishi across the university bridge on 7-28-2017 and suddenly the transmission went out and I was stuck and had no power of movement,my wife and 3 y.o.child were passengers in the car,luckily the state patrol came and assisted us.the dealer told us that this car was mechanically sound and had no problems or issues.they lied to us and by doing so they put our lives in danger.the drivers side air bag was also missing when we purchased the car.
January 12, 2005 one cold morning I noticed that the reverse gear did not go in as fast as it should it took like 1 minute to go into gear, when cold it would jolt before advancing in drive. Took it to the dealer, they did not find anything, so I picked up that same afternoon, next morning same problem. I took the car back on jan 19, left it over night and they found it took a couple of minutes to go into gear, therefore, they decided to look at the transmission, the car has been at the dealer since 1/20 thru 2/7, after several discussions they have told me it is the heating core dripping on top of the computer damaging the sensors, today 2/8 the car would not go into gear at all. …
2002 Mitsubishi Diamante engines & fuel economy
| Engine | Transmission | Drive | MPG city / hwy / combined |
|---|---|---|---|
| 3.5L 6-cyl | 4-speed automatic | FWD | 16 / 23 / 18 |
EPA ratings. Class: Midsize car.
Frequently asked questions
Is the 2002 Mitsubishi Diamante a good car?
Based on 123 owner complaints filed with NHTSA, the 2002 Diamante rates avoid: 3.7× as many complaints as a typical year of the Diamante at the same age. It is one of the Diamante years we suggest avoiding. Complaint counts don't account for sales volume or individual maintenance, so have any used car inspected before buying.
What is the most common problem with the 2002 Mitsubishi Diamante?
The a/c & heater — 69 complaints, 56% of all complaints for this model year, most often about defroster/defogger/hvac system › heater core. Next are the engine & cooling (38) and transmission & drivetrain (10).
How many recalls does the 2002 Mitsubishi Diamante have?
There are 3 recalls for the 2002 Mitsubishi Diamante, the most recent from September 1, 2004 (labels). Recall repairs are free at any authorized dealer — check whether yours has been done with the VIN recall check.
What are the best and worst years of the Mitsubishi Diamante?
The best years by complaints, compared at the same age, are 1995, 1999 and 1998. Years to avoid or approach with caution: 2002, 2001, 2003 and 2000. See the full Mitsubishi Diamante years comparison.
At what mileage do 2002 Mitsubishi Diamante problems happen?
The median mileage reported in complaints is about 62,000 miles; 29% of problems with a recorded mileage started before 50,000 miles.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.