Defogger Heater Problems of Mitsubishi Diamante - part 1

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.

See all problems of the 2003 Mitsubishi Diamante 🔎.

Foggy window, antifreeze smell through vent, passenger side floor damp/wet. Was told by dealer that heatercore o-rings and heatercore possibly needs to be replaced. Looking for alternative solution to resolve the problem.

See all problems of the 2002 Mitsubishi Diamante 🔎.

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.

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. The car is undrivable due to the toxic fumes from the ethylene glycol coming out of all the vents and I do not have the money to get it repaired. Mitsubishi refuses to do anything about it, and nearly every Diamante on the road has had this happen. The carpet is ruined from the coolant leak as well, and many have had the ecu for the transmission fail due to coolant leaking on it.

See all problems of the 1998 Mitsubishi Diamante 🔎.

The heater core. I start smelling an antifreeze smell inside the car then the check engine soon light came on. Also the tcl is on. The dealer said that it is a wheel sensor that will run me $625. The heater core is $1,200. Every one that I talk to on the email sight is having the same problem. Please help! thanks.

Started smelling "maple syrup" in passenger compartment. Windows were fogging up easily. This was confirmed by dealer to be the heater core leaking antifreeze, and service cost $1,100.

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.

Heater core is causing the windows to fog up, the car to smell like antifreeze and may be damaging the ecu. There are hundreds of posts online about people having this problem over and over with this car. It is clearly a manufacturers defect and customers are left paying thousands of dollars fo the repair.

See all problems of the 2001 Mitsubishi Diamante 🔎.

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.

Heater core went bad at 105,000 miles. This seems to be a manufactoring problem and mitsubihi should adress the issue.

The windshield fogs up for no reason and I am not able to defog it. It is very hard to see any time the heat is on. I am told it may be the heater core.

Windows are fogging up do t a faulty heater core. I really don't mind repairing the car seeing that it has 120k on it. . I purchased the car brand new and this will be the 3rd heater core!!! what's going on!.

The contact owns a 2002 Mitsubishi Diamante. The check engine light began illuminating, the heater coil was leaking, and the windows were steaming. The contact smelled a foul odor coming from the vehicle. A mechanic diagnosed that the heater core needed to be replaced. The failure mileage was 67,800 and current mileage was 67,990.

Windshield fog, sweet syrup smell.

2002 Mitsubishi Diamante 65k miles. Failure of heater core/ heater core gaskets/ o-rings. Windshield will not defog, strong coolant odor and residue on windshield and side windows. Resulted in dangerously low visibility while driving. Windshield too foggy for safe driving. Strong smell of antifreeze in passenger compt. Had to open windows in sub freezing temp to get fresh air to passenger compt while driving. Cost to repair estimated $800-$1100. Problem appears to be widespread based on complaints filed at this NHTSA site as some complaints are categorized under different component names but have same problem descriptions. Greater than 60 complaints by my count for 2002 model year alone on relatively low number of vehicles sold in us.

Heater core - the air that comes out the vent when I turn my heater on, smells like antifreeze. My windows fog up and I work at night. Its kind of hard to keep wiping down the windshield consistently with my hand while driving.

The contact owns a 1997 Mitsubishi Diamante. The contact stated that the radiator leaked due to the heater core. The radiator leaked onto the carpet when the heat was activated. The contact stated that he and his family have inhaled toxic fumes from the radiator leaking onto the carpet and they are concerned of future health risks. In order to repair the leak, the entire dashboard had to be removed. The VIN was unavailable. The current mileage was 113,000 and failure mileage was 112,000.

See all problems of the 1997 Mitsubishi Diamante 🔎.

37813 miles. Heater core leaking. Notice the sweet smell and now overheating occurs.

Fall of 2007, noticed increased fogging of windows that did not go away with defroster, fresh air. Began to smell sweet, syrupy smell. November 07, heat refused to work, checked antifreeze level, very low. Windows continuing to not be cleared. Oily film covering windows. Currently, I have not had complete failure of heater or computer module. I have researched this problem on the Diamante owners web site. My problems mirror exactly as fellow posters. November 29, 2007, I pulled back the carpet to inspect computer module and heater core area, there is gunky green ooze on the floor and on the computer module. I am currently in the position of researching the best way to have problem fixed, whether at the dealer, another auto shop, or self repair.

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!!!.

02 Diamante with approx 42, 000 ml - upon starting the car the front window begins fogging up and the entire car then fills with steam that is sweet but overwhelming. It gets so bad it is nearly impossible to see out the front windshield and then the smell overwhelms you within about 5-10 minutes forcing the driver to pull over or drive with the windows down (not easy at 18 deg outside and 2 kids under 5 in the back). Symptoms indicate that this is a heater core problem that dealers are aware of and is a very common problem that they see approx 2-3 times a month with a charge of $1000. 00 - $1400. 00 to fix and that if not fixed then the main computer for the car would short out. So just looking at 1 dealer low end numbers: 2 heater cores per month * $1200= $2400*12months = $28,800 a year per dealer for a known problem. Also medically speaking breathing anti-freeze may cause irritation of the nose and throat with headache, particularly from mists. High vapor concentrations caused, for example, by heating the material in an enclosed and poorly ventilated workplace, may produce nausea, vomiting, headache, dizziness and irregular eye movements. For healthy people this is problem what about those with compromised immune systems.

I have a heater core failure in my 2002 Diamante. I now have antifreeze leaking into my passenger side floor. I have an antifreeze smell and smoke coming from the vents in the car. I got low on antifreeze and almost overheated on the belt parkway. It is very hard to see at night because windows will fog up and defroster makes problem worse. I have been told the cars computer is positioned under the heater core so I have to hope I do not have a computer issue as my service light has gobne on as well> I have had to replace 3 engine sensors in the last few months ( the heater core issue could be the root cause). This is a very serious situation and needs to be addressed. I see alot of the complaints for this model are for this issue. There are many people with this issue.

I have a 2002 Mitsubishi Diamante. I have kept regular maintenance. I am submitting this form because of a heater core issue I am having. However I have had the following problems with this car. All these problems seem to be recurring problems that happen to many people with this model. At least that is what I find when I search the issues on the internet 1- vibration in steering wheel --this happened multiple times after taking car back to dealer-it appears there is a known issue with the rotors in this car. After having the rotors cut twice by the dealer with no long lasting success. I had to have the brakes and rotors replaced by a mechanic ( car had less the 10,000 miles when issue started happening) 2- rusted muffler--not sure if this issue happens often but after 23,000 miles I had to have my muffler replaced because there was a hole rusted through the top of it-I was told this could happen for not using the car very much in the winter time( road salt can cause the rust) 3- heater core- I know have a heater core problem in this car. I have antifreeze leaking in passenger compartment. I have an antifreeze smell in the cabin of the car. My windows fog and the defroster will not clear the windshield ( makes it worse). I am low in antifreeze because of this. My service engine light has now come on and I am told this can be caused by leaking antifreeze onto the computer which is positioned under the heater core. This issue is widely reported on the internet in many forums and seems everybody with a Diamante will eventually have this problem. I am being told this repair can cost over 1,000 dollars 4-I have had to replace 3 sensors in the engine 2 egr and 1 idle sender (cost around 1,500 dollars). This may or may not be because of the heater core issues causing the cars computer to fail.

Just recently started having really foggy windows and started to notice sweet smell coming from car when heater/defrost was turned on. Notified dealer of problem and dealer quickly identified problem as heater core defect.

My heater core requires replacement. A few weeks ago my windshield became hazy and difficult to defrost. I did not realize it was from toxic anti-freeze leaking into the car.

Symptoms: constant nauseating smell like "burnt syrup" inside cabin, fogging of windshield on dry, warm weather day. From the many other complaints filed with NHTSA, this is a classic heater core failure. Why has there not been a recall issued? this is potential serious health and vehicle operation safety issue!.

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.

The contact owns a 2001 Mitsubishi Diamante. The windows fogged up when the air and heat were activated. The passengers could smell antifreeze. The dealer stated that the heater core failed due to defective o-rings. The heater core was replaced. The current and failure mileages were 65,000.

For over 2 years now I have had problems with an odor in my 2000 diamanti and the defogger never seemed to work on the windows. A couple of weeks ago I saw something leak onto the passenger side rug but didn't' t guess that this could have something to do with the heater core. Upon taking it to my dealer I was told this was hole in the heater core that had to be fixed immediately because it was dangerous and hazardous to my health to breath the fumes that were coming out of the core. The cost would be approximately $1200. I noticed I often had headaches when I drove long distances but was very concerned when my grandchild became very car sick (which had never happened before) upon riding in my car. I still didn't associate the heater with our problems. I think this is very dangerous and something should be recalled on these. I resent that after only 40,000 miles I must spend $1200 on something that is obviously a mistake on Mitsubishi's part since it is not a wear factor.

See all problems of the 2000 Mitsubishi Diamante 🔎.

Mitsubishi Diamante infamous heater core problem antifreeze leaks into interior of car. Horrible sickening anti freeze smell, happens on an abundance of Mitsubishi cars.

My 2001 Mitsubishi Diamante's heater core went up. I have massive amounts of coolant leaking on my passenger side, thick smoke coming from my vents and a bad odor coming from the vents. I have read this is a very very common thing with Mitsubishi's especially Diamante's.

Heating core going bad, window shield fogs up and cannot wipe ways easily, vapors coming from under dash, syrup smell is strong and only when heat is on.

Heater core (and a/c condensate) leaks into passenger compartment causing window to "fog up". This could be very dangerous as it impairs the drivers sight.

2001 Mitsubishi Diamante - have antifreeze odor coming from ac vents. After much research I find that this is a recurring problem with second generation Diamantes (1997-2004) with the 2001 year model being the most effected. The odors have even caused respiratory problems. I myself have experienced severe headaches and sleepiness due to this problem. The odor at first was very faint but became worse over time. With as many problems that has occurred and the health implications related to this obvious defect, this problem should be a manufacturers recall to resolve this potentially dangerous and health hazardous issue.

Bad heater core, leaking o-rings.