2001 Mitsubishi Montero Problems

What owners report

Owners of this model year most often describe brake problems, particularly with the hydraulic brake booster and its accumulator, where a chirping or buzzing noise from the front of the vehicle is followed by a hard pedal and reduced braking assistance. Some report that a prior recall repair did not prevent the symptom from returning. Electrical complaints, mainly a horn that sounds on its own, and cooling-system engine failures are the next most common themes in the sampled complaints.

1. 1
   Brakes

   Brake booster / accumulator noise and loss of power assist

   • 57 complaints (34%)
   • median 124,352 mi at 9.7 yrs old (55 state mileage)
   • 2 mention a crash, fire or injury
   • owner-quoted repair $1,550 (median of 6 quotes)
   • filed 2003–2022

   Owners describe a chirping, buzzing, clicking, or grinding noise from the front of the vehicle or under the dash, often with brake-pedal vibration, followed by a pedal that feels hard or travels to the floor. Many say the ABS or brake warning light comes on with a chime. According to the complaints, dealers and independent shops commonly diagnosed the hydraulic brake booster or its accumulator, and several owners were told their vehicle was not covered by NHTSA campaign 01V254001 or that the prior recall repair was all that would be honored. Spread across the whole mileage range, with many reports between roughly 70,000 and 175,000 miles, and some just after a recall repair.

   Recall 01V254001

   What to check: Ask whether the accumulator recall 01V254001 was performed and keep documentation, then listen for a chirp or buzz from the front with the engine running and check that the pedal is firm and the ABS light stays off.

   2 excerpts from owner complaints in NHTSA records

   “I have a 2001 Mitsubishi Montero and it has about 135k miles, today it had ABS brake warning light came on and continuous beep came, then brakes became too hard and stopped working. I had to use handbrakes to stop the vehicle. It seems like the problem as stated in 2001 recall 01v254001. Please help me to resolve this problem.”

   NHTSA complaint #10419759, filed 2011-08, 134,000 miles

   “The brake booster accumulator is leaking so it makes a 'chirping' sound from the left side of the vehicle. This is a recognized fault with this vehicle and a recall was issued I did not get notification of the recall so did not get it fixed. It has now become a problem which I am told could cause the brakes to fail, obviously a serious safety issue. I have spoken to Mitsubishi and they will not honor the recall.”

   NHTSA complaint #11324165, filed 2020-05, 206,000 miles
2. 2
   Electrical system

   Horn sounds on its own

   • 20 complaints (12%)
   • median 128,750 mi at 10.9 yrs old (18 state mileage)
   • filed 2004–2021

   Owners report the horn blaring without anyone pressing it, sometimes at night while the vehicle is parked and locked. Several say they had to pull the horn fuse or disconnect the battery to stop it, which leaves them without a working horn. Dealers reportedly linked it to the horn contact inside the airbag assembly or to a cold-weather-sensitive trigger. Often described in cold weather, with reports from about 50,000 to 250,000 miles.

   What to check: With the engine off, confirm the horn works only when pressed and ask whether the horn fuse or relay has been pulled; on a cold morning, listen for any spontaneous honk.

   2 excerpts from owner complaints in NHTSA records

   “I have had an issue with my truck because the horn quit working several years ago. I was told by the dealer multiple times that the airbag has a metal ring inside of it that makes contact to activate the horn when pressed. They claimed the ring has either deteriorated or broken internally and that is why the horn doesn't work and is a very common issue for years with these trucks. …”

   NHTSA complaint #10649572, filed 2014-10, 100,000 miles

   “The horn on my 2001 Mitsubishi Montero limited will not stop blaring ~ had to take it in for costly repairs all the while ... Blaring down the street to my mechanic.”

   NHTSA complaint #10375074, filed 2011-01, 127,501 miles
3. 3
   Engine cooling

   Engine overheats and fails with little warning

   • 11 complaints (7%)
   • median 72,000 mi at 4.0 yrs old (9 state mileage, few)
   • filed 2001–2011

   Owners describe the engine stopping or seizing while driving, sometimes after air from the vents went cold when the vehicle stopped. Complaints mention a broken plastic tee in the heater line and a sticking thermostat, and in some cases the temperature indicator did not show overheating before the engine failed. Some reports involve repeated check-engine lights with a coolant temperature code that thermostat and sensor replacement did not resolve. Mostly reported between roughly 40,000 and 120,000 miles.

   1 related service bulletin

   What to check: Check coolant level and condition, look for a cracked plastic heater-line tee, and confirm the temperature gauge responds; ask about any history of overheating or head gasket work.

   2 excerpts from owner complaints in NHTSA records

   “2001 Mitsubishi Montero; engine shot on the highway (nj turnpike). There was no oil warning. This is a life threatening issue-if I had been on the inner lane, I would have been dead. Vehicles on nj turnpike are traveling 60-80mph. Vehicle has been serviced on timely oil changes at jiffy lube. This should not have happened. It has 90k mlies on it, bought used, I owe $15k on it, it will cost $8k to fix. 2 yrs og payments to go.”

   NHTSA complaint #10102139, filed 2004-12, 90,000 miles

   “Consumer stated that she had 70,000 miles on vehicle and the engine blew out. When driving the air would blow, then when stopping the air would stop. Consumer took the vehicle to dealer, and was told that it looked as if the plastic tee in the heater line was busted. Then, she was told that it may the thermostat that was sticking. The next day while driving the vehicle just stopped. Had vehicle towed to the dealer, and mechanic determined that motor blew out. …”

   NHTSA complaint #10090245, filed 2004-09, 70,000 miles
4. 4
   Air bags

   Airbags not deploying in a collision

   • 13 complaints (8%)
   • median 100,000 mi at 5.6 yrs old (7 state mileage, few)
   • 9 mention a crash, fire or injury
   • filed 2001–2014

   Owners describe front-end impacts and a rollover in which none of the airbags deployed. Repair shops reportedly could not determine why the bags did not fire, and one owner noted the horn contact inside the airbag assembly had failed and asked whether the bags would still work. Reported from about 50,000 to 100,000 miles, in collisions at highway speeds.

   Recall 04V428000Recall 04V067000

   What to check: Check that the airbag warning light comes on with the ignition and goes out, that the horn works, and ask whether the vehicle has been in a reported collision.

   2 excerpts from owner complaints in NHTSA records

   “While driving at 45 MPH in the rain a deer ran in front of consumer's vehicle. Consumer swerved to avoid the deer and went into a ditch. Front of the vehicle struck a metal pole in a driveway and flipped over several times. Seat belts were worn at the time of the collision, but air bags did not deploy.”

   NHTSA complaint #10072271, filed 2004-05, 130,000 miles

   “Roll over accident in 2001 Montero ltd. At 65 MPH the truck was rolled over 2.5 times and ended up resting on the passenger side. Of the four airbags available, not one deployed. The drivers side rear passenger exterior door skin, passenger side front interior and exterior door skins were completely removed. The roof was resting on the steering wheel. Passenger side windshield pillar separated at body. Drivers side headrest bent at 90-degree angle towards hood. Pictures available upon request.”

   NHTSA complaint #10062476, filed 2004-03, 69,000 miles

Buying note. Have a pre-purchase inspection focus on the brake booster and accumulator, including recall 01V254001 history, plus the horn circuit and cooling system. Service records showing completed recall work and cooling-system maintenance are worth asking for on a vehicle of this age.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.