Unfortunately our decision to buy a new Toyota Landcruiser Prado for our tour around Australia has turned out to be a bad one. It seems that recent developments in engine monitoring technology have lead to a regression rather than an improvement in its utility as an off-road vehicle for touring remote parts of Australia.
While we are normally reluctant to publish negative matters on this blog, we understand that several people are following our blog with the aspiration of doing something similar to us and we feel that they should be aware of our experience in this case.
On opening the bonnet of the latest Prado one is immediately stuck by the number of wires connected to a myriad of sensors attached to various parts of the engine. When I took delivery of the Prado I certainly wondered what would happen if one of the sensors malfunctioned. Well we have had such an experience, which over the last few months has cost us dearly in wasted time and missed opportunities. However, the truly frustrating thing is that it was not a faulty sensor that caused our woes (in fact the sensor was valid in reporting a compromised situation*) but that the car’s designed reaction to that sensor’s input is so totally inappropriate. What is even more frustrating is that despite prolonged discussions with Toyota, they don’t seem to feel that there is anything wrong with the current design. So on reading this please let me know if you come to the same conclusion as I do (or if you feel Toyota is right).
* We have also learned that the actual compromised situation is caused by a known design flaw that has been reported in the media: https://www.carsales.com.au/editorial/details/toyota-strikes-diesel-and-dust-drama-113482/ Incredibly not only did Toyota not proactively raise this to us when discussing our problems, but even went as far as lying about the problem and saying that we were the first to raise this issue with them. Given this mind-boggling arrogance and dishonesty, we would now go further: don’t just avoid buying a Prado, avoid buying a Toyota – period.
Prior to publishing this (and prior to becoming aware of the known design fault with the air filter), I sent the wording below to Toyota to give them the opportunity to correct any possible misunderstandings, however they have not responded.
We first became aware of a problem when cruising on an open sealed road and the car suddenly let out a bong and the words “check engine”; “pre-crash safety malfunction”; “reduced engine power”; “visit your dealer” appeared on the console. At the same time the corresponding indicator lights for the engine, pre-crash safety system as well as the traction control system came on. So we stopped and looked at the engine, but could not see anything obviously wrong. Knowing that the pre-crash safety system relies on a radar mounted behind the Toyota logo on the front of the car and a windscreen mounted camera and both were a bit dirty, I cleaned both and restarted the engine. After this, the words “reduced engine power” were no longer appearing and the engine power certainly felt normal, however the “check engine” and “pre-crash safety malfunction” messages were still there, so we abandoned our immediate touring plans and headed as directly as we could to the closest Toyota dealer which was about 400km away.
To cut a long story short, we have now experienced this problem 3 times and after 3 inconvenient visits to get it fixed and numerous calls to Toyota we have developed the following understanding of the problem.
One of the many sensors in the engine is the mass airflow sensor (MAF sensor). It sits just behind the air filter and is intended to monitor if too much dust has managed to get past the air filter. Toyota tells us that when this sensor triggers, it reduces engine power (to protect the engine) and disables the traction control system. The pre-crash safety system (a technology to automatically apply the brakes if the car detects an obstruction ahead) in turn relies on the correct functioning of the traction control system, so this is therefore also disabled.
So basically the messages “check engine” and “pre-crash safety malfunction” are related to dust in the air intake !?!
To me a far more informative message would be “dust detected in air intake”. When I suggested this, one person at Toyota gave me the excuse that with all the inputs from many sensors it is hard to design a system that can correctly report all types of faults. Seriously? In an age where car makers are developing driverless cars is it really too hard for a system to conclude that when the sensor that detects dust in the air intake triggers, that the likely cause might well in fact be dust in the air intake? Furthermore for a car that is purported to be suited to off-road travel, and hence be expected to travel on dusty roads shouldn’t it be even more important to get this right? I have raised this with Toyota but have been told that their technical experts have reviewed our case and concluded that nothing needs to be changed.
I was also told that the car is designed to limit power when this sensor triggers “to protect the engine”. Yes, this did happen initially, but as soon as I restarted the car after these messages first appeared (and all subsequent starts) it resumed operating at normal power. Now if Toyota’s intent was to protect the engine, surely a more appropriate way to do this would be to advise the driver that there is dust in the air intake so that they could decide on an appropriate course of action to actually protect the engine – like changing the air-filter (or at least cleaning it). Again, for a car that is purported to be suitable for off-road use in remote areas, Toyota should understand that it is not possible to simply drive up the road and visit a dealer so why not give the driver the opportunity to proactively prevent further dust damage in the meantime? However, I am told that their technical experts again disagree and in one call was told rather patronisingly that by changing an air filter I could risk allowing something to drop into the engine that could result in serious damage. Firstly, this would be extremely difficult to achieve as air is drawn upwards through the filter so whatever it is, would have to be deliberately thrown upwards to get towards the engine. Secondly there is a barrier that would prevent all but the smallest of items going through anyway and thirdly, anyone who is familiar enough with engines to change an air filter will know to be cautious.
When I asked why the detection of dust in the air intake requires the traction control system (and hence pre-crash safety system) to be disabled. I was given an explanation to the effect that “multiple systems get disabled to protect the engine”. Again, for a car that is purported to be appropriate for use in remote areas where the owner probably needs to drive several hundred kilometers to visit a dealer, why disable systems that are designed to increase the safety of the occupants? On this matter, like before, I have been told that Toyota’s technical experts have reviewed this and conclude that nothing needs to be changed.
While one could hope that our experience with this one issue is an exception, the fact that Toyota’s technical experts have reviewed this case and come to the conclusion that nothing needs to be changed (or so I am told), makes me wonder how many other algorithms in Toyota’s electronic engine management and supervisory systems are either half-baked or designed by people in ivory towers. The fact that Toyota is facing a class action over an issue with their diesel particulate filters further affirms to me that they have lost the edge where it comes to such things and also appear to initially adopt a position of denial and attempt to brush things under the carpet when problems are first raised.
So in this light I can only conclude that the designers of the Prado have the mindset that it is only going to be used on sealed roads where dust is not a common issue and operated close to cities or major regional towns so that you can easily visit a dealer whenever one of its sensors feels a bit uncomfortable and causes it to throw up a random message or warnings.
It reminds us a bit of the story of the princess and the pea so we have decided to rename our car “Princess” – we even found a suitable bumper sticker at a roadhouse. S
Very pathetic! A four wheel drive that complains about dust! Hope there is a Toyota dealer on the Birdsville track!!!! M