Toyota Hilux, Fortuner and Prado affected by air-intake system fault (Australia)

Ivan Leon

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Toyota’s reputation for reliability and suitability to Australian roads is being called into question following successive 4X4 Australia tests that uncovered a fault with the air intake system of the Hilux, Fortuner and Prado.

During a recent outback adventure involving the new Hilux Rugged X – the top-of-the-range model claimed to “build on the ‘unbreakable’ reputation of the Hilux” – on four occasions the car triggered a limp-home mode on the engine and disconnected key active safety systems, including stability control.

It follows on from an identical fault in a Fortuner during a 2016 test in the Northern Territory.

Toyota has confirmed the design fault also affects the Prado, in total affecting about 170,000 cars fitted with the latest generation 2.8-litre four-cylinder turbo diesel engine.

Toyota has known about the issue for at least two years, tracking it to dust getting past the air filter and into the mass airflow sensor (MAF), in turn instructing the engine control unit to reduce power and shut down some safety systems.

“It has now been raised as a design issue with Toyota in Japan,” a spokesman told 4X4 Australia. “They will be working on a redesign of the air intake system.”

However, Toyota has no plans to fix the fault in existing cars, instead working on a new air-intake to be introduced to a future update to the Hilux, Fortuner and Prado.

“There are no plans to replace the air filters. Standard maintenance and replacement of filters will continue to occur, and in severely dusty operating conditions Toyota dealers have been advised of the additional maintenance requirements that need to be followed.”


In some cases Toyota is instructing owners to check air intakes more frequently.

“It’s important that the air filter is checked more regularly in extremely dusty conditions … it’s an easy fix to have dust blown out (to clean the sensor).”

A dealer bulletin distributed in March 2017 also instructs dealers to perform additional checks and cleaning for vehicles driven in dusty conditions.

However, owners are not being actively informed of how to reduce the chances of their cars throwing up warnings and reducing power, potentially leaving them underperforming in the rugged, remote conditions they were designed to operate in.

Nor are they instructed what to do if their car throws up the warnings; the recommendation is simply to visit a dealer.


As any number of rural Toyota owners and outback adventurers know, that’s often easier said than done.

For anyone who does experience the fault, we managed to reset the electrical systems by disconnecting then reconnecting the battery.

Link: https://www.whichcar.com.au/news/toyota-hilux-fortuner-and-prado-air-intake-system-fault
 

Ivan Leon

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Toyota is refusing to repair a known flaw with up to 170,000 Hilux, Fortuner and Prado off-roaders in Australia.

The design fault can lead to dust intrusion in the air intake leading to significantly reduced engine power and the disconnection of active safety systems – often while driving in rural and remote areas.

The top-selling Hilux – marketed as “unbreakable” and sold on its reliability and suitability to Australian conditions – is prone to the dust intrusion, something that can trigger a limp-home mode that in turn drops engine power and directs owners to visit their dealer.

The issue also affects the Fortuner and Prado, which use the same 2.8-litre engine first introduced in 2015.

More than 170,000 cars could experience the fault, which can occur in dusty driving and lead to fine particles infiltrating the clean side of the air intake system, becoming statically charged and attaching themselves to the mass airflow sensor (MAF), which is used to measure intake air quality.

When that sensor detects dust, it sends a message to the car’s electronic control unit instructing it to reduce power.

The car also disconnects safety systems, including traction control and stability control, features now mandatory on all new cars to help control a skid.


Fairfax has now experienced the fault in two cars – a Fortuner and Hilux – at times when overtaking at more than 100km/h.

The problem has been traced to the design of the air intake system; along with the rest of the car it underwent extensive testing and development on Australian roads.

Toyota has known about the problem since at least 2016 and in March 2017 issued a dealer bulletin instructing dealers to inspect and clean parts of the air filters of affected cars using compressed air.

However, owners are only being informed of the issue if they question a dealer – and if the dealer representative is aware of the bulletin.

While Toyota is working on a fix for future cars, there are no plans to repair existing cars.


“It has now been raised as a design issue with Toyota in Japan,” a spokesman told Drive. “They will be working on a redesign of the air intake system.”

Toyota confirmed it is not planning to replace the parts on affected vehicles – despite the potential to leave drivers with an underperforming car.

“There are no plans to replace the air filters,” the spokesman said. “Standard maintenance and replacement of filters will continue to occur and in severely dusty operating conditions Toyota dealers have been advised of the additional maintenance requirements that need to be followed.”

For those driving in dusty conditions, Toyota is recommending owners check and clean their air filters more regularly – or visit their dealers more often.

“It’s important that the air filter is checked more regularly in extremely dusty conditions … it’s an easy fix to have dust blown out (to clean the sensor).”

In certain situations – once the redesigned intake is available - Toyota also says it may look at retrofitting the redesigned air intake at no cost to the owner.

Ironically, the issue is amplified when the car is equipped with a snorkel, something fitted to the most off-road focused Hilux, the recently-unleashed Hilux Rugged X.

Snorkels are also typically fitted by off-roaders looking to drive through water or in dusty conditions (in the owner’s manual Toyota says the snorkel “is designed to provide cleaner air to the engine in dusty conditions”).

Toyota instructs owners driving in “extremely dusty conditions” to reverse the head of the snorkel and face it towards the rear of the car, something that requires loosening two screws.


Defending its stance on not replacing faulty cars, Toyota says the issue occurs in “really, really dusty” conditions.

However, that is exactly the environment the Hilux, Fortuner and Prado are designed to drive in.

The front page of the brochure for the Hilux features a car kicking up rocks and dust in the outback.

In the same brochure – which features pictures of cars on red dirt – Toyota describes the Hilux Rugged X as “an uncompromising combination of off-road capability and urban credibility”.

Despite dropping power and disconnecting safety systems Toyota says there are no plans to recall the cars.

“As the vehicle is subject to reduced engine power (‘limp mode’) and can continue to be operated safely, it is not a safety related item that would require a recall. We do however encourage customers to contact their nearest dealer as soon as possible if this issue does present itself.”



Link: https://www.drive.com.au/motor-news/toyota-refuses-to-fix-hilux-fault-118750
 

Ivan Leon

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An intake problem with the turbo-diesel engine in the top-selling Toyota HiLux ute — which was identified during a motoring.com.au comparison test, triggers ‘limp-home’ mode and turns off safety features including stability control — will be the subject of an urgent redesign in Japan.

But Toyota Australia cannot yet confirm if the solution will be offered as a retrofit for the 170,000-plus Toyota HiLux, Fortuner and Prado vehicles already on local roads with the 2.8-litre four-cylinder turbo-diesel engine.

And it is refuting suggestions this is a safety issue that requires a recall to fix, or that engine longevity could be affected.

“As the vehicle is subject to reduced engine power and can continue to be operated safely, it is not a safety related item that would require a recall,” a Toyota Australia spokesperson told motoring.com.au in a statement.

The design flaw allows dust to leak past the air-filter and corrupt the readings the mass air-flow sensor (MAF), which measures the rate of air entering the direct-injection engine. The engine control unit (ECU) uses the reading to determine the correct air/fuel ratio.

The corrupted data prompts the engine to go into limp-home mode — a potentially dangerous outcome in the wrong situation, such as when overtaking.

It also turns off the stability and traction control systems and, depending on the instrument panel fitted to the vehicle, instructs the driver to visit a Toyota dealer or consult the owner’s manual.


“The vehicle takes a conservative approach and disables the safety systems entirely instead of making an inaccurate judgment using incorrect or incomplete data,” the spokesperson explained.

The engine in our test HiLux Rugged X went into limp-home mode four times without any warning. It was temporarily fixed each time by disconnecting and reconnecting the battery.

But motoring.com.au is also aware of a Fortuner press vehicle having the same problem. That vehicle went into limp-home when the driver was attempting to pass a B-double on an outback road.

The problem is a major embarrassment for Toyota, which prides itself on its reputation for quality and reliability and markets the HiLux as ‘unbreakable’.

In essence, three vehicles promoted for their off-road use have a design fault that affects their capability to perform in that environment.

The HiLux has been Australia’s top-selling vehicle for the last two years and the Prado has been the nation’s most popular large SUV for longer.

The downsized 1GD-FTV turbo-diesel in question made its Australian debut in the Prado in August 2015, shortly before appearing in the current HiLux and Fortuner in October 2015.

More than 170,000 vehicles fitted with this engine are now on Australian roads.

“The dust that makes its way through the filter is very fine and typically less than five microns in size. What can occur is that these very fine particles attach themselves to the sensor electrostatically,” the Toyota spokesperson said.

“It is not an issue of the dust finding their way into any internal components of the MAF sensor.”

While Toyota Australia is only publicly acknowledging the issue in the wake of our test, it issued service bulletins to dealers as far back as March 2017.

At that stage it advised dealers that the HiLux, Fortuner and Prado required air-filter cleaning more often when they are used in dusty conditions.

The bulletin also recommends an additional two-minute procedure to blow compressed air past the MAF sensor.

Owners are also being made aware of the issue and being advised to clean the air-filter more often.


“It’s important that the air-filter is checked more regularly in extremely dusty conditions … it’s an easy fix to have dust blown out [to clean the sensor].”

It has also been found that an air snorkel, such as the one fitted to the Rugged X we tested, can exacerbate the problem in dusty conditions.

Toyota says that issue can be reduced by turning the intake rearward, a recommendation it makes in the owner’s manual.


But the real fix is a redesign of the air inlet system and that is happening in Japan.

“We have provided details of the experiences in the field in Australia to our head office in Japan and they will be making design changes to improve the performance of the air intake in extremely dusty conditions at the earliest possible opportunity,” the spokesman confirmed.

The redesigned air intake’s introduction timing is unknown.

“Any change to the intake system will affect emissions and homologation and therefore will require extensive retesting,” said Toyota.

“At this stage we believe it will not make it in time for the next technical change but we will endeavour to expedite this so it is implemented at the earliest production opportunity."

“We have requested that any changes to the air intake or other related systems be made available also to vehicles already in the field."

“However, as the design is not yet complete, it is too early to say whether this will be possible.”


Toyota will retrofit parts free of charge, the spokesman said, but is playing down the extent of the limp-home issue, saying it strikes only rarely and only in “extremely dusty” conditions.

It also downplayed the prospect of engine damage from dust ingress.

“The dust particle size that passes through the air intake system can become statically charged and adhere to the MAF sensor,” said Toyota.

“The size of these particles is around two microns. In general this type of very fine dust is not known to cause engine damage.”

Link: https://www.motoring.com.au/toyota-strikes-diesel-and-dust-drama-113482/
 
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