Mitsubishi Montero Sport: Common issues and how to fix them

Updated Nov 18, 2022 | Same topic: Handy Maintenance Tips

From gunky intake manifolds to bad alternators.

Being a seven-seater midsize SUV, the Mitsubishi Montero Sport has maintained itself to be a popular model in the Philippine market. People like it for its exterior design, and of course the interior space it provides.

A picture of the Mitsubishi Montero Sport

The Mitsubishi Montero Sport

On top of that, the Mitsubishi Montero Sport has good reliability in general. The current one available on the local market is built on the proven Strada/Triton body-on-frame chassis and it also uses the robust 2.4-liter 4N15 MIVEC inline-4 turbodiesel. An engine from the 4N1 series, which in turn has been around since the early 2000s.

Like any car however, the Mitsubishi Montero Sport will encounter issues in the long run. These issues of course are similar to other modern turbodiesel models. So what are these issues and how does one fix them?

A picture of the Montero Sport's Super Select II 4x4

Generally, the 4x4 system on the Montero Sport doesn't have much problems

Mitsubishi Montero Sport: Common Problems

Gunk in the intake

Being a modern diesel SUV, the Mitsubishi Montero Sport will eventually experience gunk build-up in its exhaust gas recirculation (EGR) valve and intake manifold. If left alone, this can incur more damage to the engine’s internals.

A clogged up EGR valve.

A clogged up EGR valve. Yuck

To understand this, the 4N15’s EGR takes a small portion of the exhaust gasses to clean it up by burning it. This of course results in oily soot. Now the said soot is likely to combine with the oily gas coming out from the crankcase. Whenever this two mix, it results in a very sticky substance that will gunk up your Montero Sport’s intake manifold and EGR valve.

With those clogged up, it will result in a check engine light, and acceleration problems. Moreover, your SUV might experience trouble reaching peak power as the gunk blocking it from receiving the necessary air to effectively burn its fuel.

Loose valve clearances

The 4N15 is a turbodiesel mill that uses a shim-over-bucket valve adjuster. To be specific, the upside-down “bucket” and shim are devices that set the height of the engine’s valve springs. Now the issue is, these valve shims will get loose over time and so they can no longer keep the right valve clearance. They get loose over time because the valve shim is in constant friction. As such it will get thinner and thinner every time you use your Montero. The same is also the case with other cylinder head components like the valve bucket.

A picture of the the Montero Sport's 4N15 engine

The 4N15 is tough, but wear and tear will affect it eventually

If you insist on running an engine without the proper valve clearance, this may result in damaged valves, or worse, upper-cylinder damage. That of course involves an engine rebuilt, which will surely destroy your wallet.

And yes, the 4N15 has variable valve timing. As such, this means that having the right valve clearances is crucial to its operation.

Faulty alternators

Like any vehicle, an aging Mitsubishi Montero Sport might get alternator problems. Common causes of a failing alternator include the wear and tear of parts, bearing failure, and wiring problems. Any of these issues can be detected by flickering lights, strange noises, stalling, or difficulty in starting.

Mitsubishi Montero Sport: Troubleshooting

How to fix intake clogging

To fix a Montero Sport’s clogged intake, one has to manually clean it. To do this, you’ll need to disassemble the intake valve, and locate the EGR valve. Once done, you can use a commercially available cleaner spray that will get rid of the gunk. If the clog is bad enough that it has reached beyond the confines of the intake manifold, you might have to take your Montero to a diesel specialist.

A picture of an aerosol valve cleaner spray

Valve cleaners like this one from Liqui Moly is enough

In the event that you decide to fix this problem yourself, please don’t forget to wear gloves and eye protection. And yes, diesel gunk is not something you’d want on your skin and eyes.

How to fix loose valve clearances

In the olden days, one can readjust an engine’s rocker arms to get the right valve clearances. This can be done by ear and minimal tools. The Montero Sport however, is a modern turbodiesel that uses common-rail injection. And yes, the 4N15’s variable valve timing only serves to complicate things. To this end, we recommend acquiring the help of a proper mechanic. One that’s thoroughly familiar with the 4N15.

Luckily for you, Mitsubishi recommends that one should have his/her Montero Sport’s valve clearances checked every 30,000 km. So if you followed this to heart, you won’t be having valve clearance issues at all.

How to fix a Montero Sport’s alternator problems

If you want to save on money, one way to fix a Montero Sport’s alternator is to have it checked by an automotive electrician. In the local setting, the said electrician might be able to jury-rig a fix, aka “recondition” your alternator. This however, in most cases, is a temporary solution. Instead, we recommend ordering a new alternator, if the problem was indeed traced to the alternator’s interior parts in the first place.

If the problem was merely caused by wiring problems, then an automotive electrician will do.

A picture of the 4N1 engine

As a side note, do remember that you also have to maintain the Montero's belts

Did this help you in any way? Are there other common Montero Sport issues you want us to talk about?

For more car maintenance tips, as well as car buying tips, keep it here on If you are interested in getting a new Mitsubishi Montero Sport, check out Montero Sport price Philippines.

Know more about Mitsubishi Montero Sport 2023

Mitsubishi Montero Sport

One of the popular midsize SUVs in the Philippines is the Montero Sport by Japanese auto giant Mitsubishi. It continually hits the list of best-selling cars in the country every year. Mitsubishi Montero Sport 2023 price in the Philippines is quite good, ranging from PHP 1,568,000 to PHP 2,341,000 with five variants. Powering this midsize SUV is a 2.4-liter 4N15 inline-4 Mitsubishi Innovative Valve Timing Electronic Control (MIVEC) that makes 179 hp and 430 Nm of torque. It can send power to all four wheels via either a 6-speed manual or 8-speed automatic with Sports Mode. The Montero Sport spans 4,825 mm in length, 1,815 mm in width, and 1,835 mm in height. Currently, this Mitsubishi vehicle is competing against the Toyota Fortuner, Isuzu mu-X, and Ford Everest.

The Mitsubishi Montero Sport, as a third-generation model, displays its benchmark for the brand's contemporary lineup, which is the 'Dynamic Shield' grille that shows a completely redesigned front. Similar to the model it replaced, the Mitsubishi Montero Sport is L200 or Strada pickup based. The chassis and half of its front body structure are the same as its pickup sibling. It still uses the three-link live axle coil spring for the rear suspension and the independent double-wishbone front suspension from the model it supersedes. The full list of Mitsubishi Montero Sport for sale of car dealers on gets 82 results, you can take a look to make a wise choice yourself.

₱ 1,568,000 - ₱ 2,366,000

Cesar G.B. Miguel

Cesar G.B. Miguel


Cesar Guiderone B. Miguel was born and raised in Iligan City, Lanao Del Norte. He graduated in 2010 with a Bachelor of Arts in English degree from Mindanao State University - Iligan Institute of Technology. He previously worked as a freelance writer for various websites, as a member of the Iligan City Disaster Risk Reduction Management's training staff, and as a medical sales representative.


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