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2003 Mitsubishi Diamante

Owner reports · Recalls · Investigations

Similar to other model years

Owner complaints for the 2003 Mitsubishi Diamante do not stand out strongly from the model-year median of 31.5.

About this comparison →

How this year compares

Owner complaints by model year

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Counts vary with age, sales and reporting. They are not failure rates.

What owners reported most

All reported categories

Tap a category to read its complaints. One report may name several components.

When problems were reported

Mileage at the reported incident

44 reports with mileage · 12 unknown

NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.

What to inspect

Issues worth paying extra attention to based on owner reports.

  • Visibility. Review the 28 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Engine And Engine Cooling. Review the 17 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Power Train. Review the 4 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

1 crash reports0 fire reports1 injury reports

Visibility complaints

28 reports
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48,000 miles · Mar 22, 2010
Visibility

INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6). THIS CONCERNS MY 2003 MITSUBISHI DIAMANTE. IT HAS LESS THAN 50,000 MILES ON IT AND IT HAS SUDDENLY STARTED SPEWING A LIGHT FILM ON THE INSIDE OF MY FRONT WINDSHIELD SO THAT I CANNOT SEE WELL...AND NOT AT ALL WHEN I AM HEADED INTO THE …

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INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6). THIS CONCERNS MY 2003 MITSUBISHI DIAMANTE. IT HAS LESS THAN 50,000 MILES ON IT AND IT HAS SUDDENLY STARTED SPEWING A LIGHT FILM ON THE INSIDE OF MY FRONT WINDSHIELD SO THAT I CANNOT SEE WELL...AND NOT AT ALL WHEN I AM HEADED INTO THE SUN. I HAVE CHECKED ON THE INTERNET AND A LOT OF PEOPLE ARE HAVING THE SAME PROBLEM WITH MITSUBISHI DIAMANTES GOING BACK SEVERAL MODEL YEARS. ALL DIAMANTES NEED TO BE RECALLED AND THE HEATER CORE AND/OR ITS O RINGS FIXED OR REPLACED. IF THIS DOESN'T HAPPEN, PEOPLE WILL DIE WHEN THEY SUDDENLY CANNOT SEE THE ROAD THROUGH THEIR FRONT WINDSHIELD. [XXX] *TR *DT

NHTSA ODI #10321417

62,000 miles · Mar 11, 2010
Engine And Engine CoolingVisibility

I HAVE A 2003 MITSUBISHI DIAMANTE WITH 60,000 PLUS MILES. FOR THE PAST SEVERAL MONTHS I HAVE NOTICED A STRONG SMELL OF ANTI-FREEZE COMING FROM THE VENTS AND THE WINDOWS CONSTANTLY FOGGING UP, SOMETIMES TO THE POINT THAT I CANNOT SEE TO DRIVE. I HAVE READ MANY SIMILAR COMPLAINTS AND AGREE WITH OTHERS THAT MITSUBISHI NEEDS TO ISS…

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I HAVE A 2003 MITSUBISHI DIAMANTE WITH 60,000 PLUS MILES. FOR THE PAST SEVERAL MONTHS I HAVE NOTICED A STRONG SMELL OF ANTI-FREEZE COMING FROM THE VENTS AND THE WINDOWS CONSTANTLY FOGGING UP, SOMETIMES TO THE POINT THAT I CANNOT SEE TO DRIVE. I HAVE READ MANY SIMILAR COMPLAINTS AND AGREE WITH OTHERS THAT MITSUBISHI NEEDS TO ISSUE A RECALL FOR THE HEATER CORE, AS I AM SURE THIS IS THE PROBLEM. I HAVE YET TO TAKE MINE IN TO GET IT REPAIRED, SO I DON'T HAVE A COST QUOTE AT THIS TIME. *TR

NHTSA ODI #10318872

60,000 miles · Feb 16, 2010
Engine And Engine CoolingVisibility

ANTI-FREEZE LEAK ON CARPET PASSENGER SIDE NEAR FIREWALL FOGGED UP WINDOWS CHECK ENGINE LIGHT COMES ON AND OFF DUE TO THE LEAK THE ECU STARTED WORKING AWFUL. *TR

NHTSA ODI #10311071

85,000 miles · Oct 18, 2008
Visibility

HEATER CORE LEAKAGE CAUSING SMOKE AND ANTIFREEZE ODOR TO COME OUT OF CAR VENTS AND UNDERNEATH DASH BOARD (PASSENGER SIDE). THERE IS A RISK OF ACCIDENT, PERSONAL INJURY, OR DEATH BECAUSE USE OF A/C, HEATER, AND DEFROST IS NOT AVAILABLE WHEN WINDSHIELDS AND WINDOWS FOG UP. *TR

NHTSA ODI #10245996

84,900 miles · Apr 7, 2008
Visibility

DRIVING ALONG AND WINDOWS STARTED TO FOG UP, AND STARTED SMELLING A ODD ODOR. FOUND OUT MY HEATER CORE WAS BAD. APPARENTLY CRACKED FOR NO REASON. RIGHT NOW BY-PASSED THE HEATER CORE BECAUSE MITSUBISHI DEALER QUOTED $1,800.00 TO FIX IT. IT APPEARS TO BE A BIG PROBLEM WITH THE DIAMANTE'S. *TR

NHTSA ODI #10223547

20 miles · Apr 7, 2008
Engine And Engine CoolingVisibility

I HAVE 2003 MITSUBISHI DIAMANTE. MY "CHECK ENGINE" LIGHT CAME ON, SO I TOOK IT IN FOR SERVICE, AND MY HEATER CORE WAS LEAKING ON MY COMPUTER...NOW IT'S GOING TO COST ME AROUND 3,500 DOLLARS....THIS IS A VERY FLAWED DESIGN. THERE SHOULD BE A RECALL ON THIS ITEM. *TR

NHTSA ODI #10223524

Mileage unknown · Mar 18, 2008
Visibility

I BOUGHT AN 2003 MITSUBISHI DIAMANTE IN 2005. MY WIFE AND I NOTICED AN OCCASIONALLY "SYRUP" SMELL, BUT DIDN'T THINK MUCH OF IT. THIS WEEK END (MARCH 08)ANTI-FREEZE (COOLANT) BEGAN TO COME OUT OF THE VENTS IN A MIST. IT EVEN TURNED THE BOTTOM HALF OF MY FRONT WINDSHIELD GREEN CREATED A FILM ON THE WINDOWS WHICH MADE IT HARD TO SE…

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I BOUGHT AN 2003 MITSUBISHI DIAMANTE IN 2005. MY WIFE AND I NOTICED AN OCCASIONALLY "SYRUP" SMELL, BUT DIDN'T THINK MUCH OF IT. THIS WEEK END (MARCH 08)ANTI-FREEZE (COOLANT) BEGAN TO COME OUT OF THE VENTS IN A MIST. IT EVEN TURNED THE BOTTOM HALF OF MY FRONT WINDSHIELD GREEN CREATED A FILM ON THE WINDOWS WHICH MADE IT HARD TO SEE. I HAVE A NEW BORN CHILD THAT IS NOW SICK AS WELL MYSELF AND MY 2 1/2 YEAR OLD. THEY HAVE A DOCTORS APPOINTMENTS TOMORROW AND I HOPE THEY ARE NOT SICK FROM THE CAR. ESTIMATED COST TO FIX WAS ABOUT $1150. *TR

NHTSA ODI #10221561

67,000 miles · Dec 23, 2007
Visibility

I OWN A 2003 MITSUBISHI DIAMANTE LS WITH 70,000. I PURCHASED THE CAR FROM THE DEALERSHIP BRAND NEW. IN NOVEMBER 2007, THERE WAS A STRONG SMELL OF ANTIFREEZE IN THE CAR. AFTER SOME INVESTIGATION, IT WAS DISCOVERED THERE WAS A LEAK IN THE HEATING CORE, WHICH WAS CAUSING THE ANTIFREEZE TO LEAK OUT OF THE COMPARTMENT AND INTO THE…

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I OWN A 2003 MITSUBISHI DIAMANTE LS WITH 70,000. I PURCHASED THE CAR FROM THE DEALERSHIP BRAND NEW. IN NOVEMBER 2007, THERE WAS A STRONG SMELL OF ANTIFREEZE IN THE CAR. AFTER SOME INVESTIGATION, IT WAS DISCOVERED THERE WAS A LEAK IN THE HEATING CORE, WHICH WAS CAUSING THE ANTIFREEZE TO LEAK OUT OF THE COMPARTMENT AND INTO THE CABIN OF THE CAR...NEEDLESS TO SAY, THE CAR IS UNDRIVEABLE BECAUSE OF THE HEALTH RISKS ASSOCIATED WITH BREATHING ANTIFREEZE. ESTIMATED REPAIRS ARE AROUND $1500. THIS IS COMPLETELY RIDICULOUS!!!! I AM OUTRAGED TO SEE THAT SO MANY 2003 DIAMANTE OWNERS ARE HAVING THE SAME PROBLEM. I BELIEVE AN INVESTIGATION NEEDS TO BE CONDUCTED, AND MITSUBISHI MOTORS SHOULD BE HELD ACCOUNTABLE FOR THIS!!! *TR

NHTSA ODI #10212610

37,813 miles · Dec 19, 2007
Visibility

37813 MILES. HEATER CORE LEAKING. NOTICE THE SWEET SMELL AND NOW OVERHEATING OCCURS. *TR

NHTSA ODI #10212356

86,000 miles · Dec 8, 2007
Engine And Engine CoolingVisibility

THIS IS A MITSUBISHI DIAMANTE 2003 ES. I'M EXPERIENCING A SWEET SMELL OF ANTI-FREEZE INSIDE THE CAR AS SOON AS I TURN ON HEATING. ANTI-FREEZE CONTAINS ETHYLENE GLYCON AND THE FUMES ARE HIGHLY TOXIC. FIXING THE HEATER CORE WILL COST $1300. I AM FILING THIS COMPLAINT TO ASCERTAIN THAT THIS IS A VERY VERY COMMON PROBLEM IN MITSUBI…

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THIS IS A MITSUBISHI DIAMANTE 2003 ES. I'M EXPERIENCING A SWEET SMELL OF ANTI-FREEZE INSIDE THE CAR AS SOON AS I TURN ON HEATING. ANTI-FREEZE CONTAINS ETHYLENE GLYCON AND THE FUMES ARE HIGHLY TOXIC. FIXING THE HEATER CORE WILL COST $1300. I AM FILING THIS COMPLAINT TO ASCERTAIN THAT THIS IS A VERY VERY COMMON PROBLEM IN MITSUBISHI DIAMANTE AND MITSUBISHI MOTORS SHOULD BE AWARE OF THREE MAIN RISK ASSOCIATED WITH THIS: (1) THE DEFECT EXPOSES CUSTOMERS TO UNUSUAL LEVEL OF TOXIC ETHYLENE GLYCOL WHICH SHOULD NOT EXCEED 10-25 PPM LEVELS (CONSULT MSDS FOR ETHYLENE GLYCOL) (2) THE LEAK CAN AFFECT THE CAR'S MICROPROCESSOR AND POSES A SEVERE HAZARD FOR DRIVERS. (3) FAULTY HEATER CORE MAKES THE VISIBILITY DIFFICULT DUE TO FOGGING OF WINDSHIELD THUS PUTTING THE DRIVER AT GREATER RISK. I WILL EVENTUALLY FIX THE PROBLEM BY SPENDING $1300 IF MITSUBISHI REFUSES TO ISSUE A RECALL. RIGHT NOW I AM TRYING SOME RADIATOR ANTI-LEAK TO DELAY THE COSTLY REPAIR. BUT I WANT NHTSA TO BE AWARE OF THE HAZARDS THAT HAS BEEN IGNORED BY THE MANUFACTURER. *TR

NHTSA ODI #10211220

Official recalls

2

04V428000 · Equipment:other:labels

Sep 1, 2004

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.

Consequence & remedy

Consequence: THIS DOES NOT MEET THE 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. IN ADDITION, ALL CURRENT 2000-2004 NATIVA OWNERS WILL ALSO RECEIVE REPLACEMENT AIR BAG ALERT LABELS FOR THE SUN VISORS. THIS RECALL IS EXPECTED TO BEGIN DURING MARCH OR APRIL 2005. THE NOTIFICATION TO THE NATIVA OWNERS IS EXPECTED TO BEGIN DURING APRIL OR MAY 2005. OWNERS SHOULD CONTACT MITSUBISHI CARIBBEAN AT 1-787-251-8715.

04V067000 · Equipment:other:owners/service/other Manual

Feb 11, 2004

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.

Consequence & remedy

Consequence: IF THE TETHER STRAP IS IMPROPERLY INSTALLED TO THE TETHER ANCHOR, THE CHILD SAFETY SEAT MAY NOT BE SUFFICIENT RESTRAINED. IN THE EVENT OF A CRASH, THE CHILD COULD BE INJURED.

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. THE RECALL BEGAN ON MARCH 29, 2004. OWNERS SHOULD CONTACT MITSUBISHI AT 1-888-648-7820.

Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗

NHTSA investigations

0

No exact-year investigations in this snapshot.