Mechanical Repairs
The Prius hybrid is very reliable mechanically. Over the 5 years that we have been involved with the Prius hybrid we have worked on over 300 vehicles and have seen only 1 with a transmission problem. We have also come across 1 other vehicle that have run for more than 2 months with no engine oil. This vehicle is still working.
The reason why this vehicle is so mechanically reliable is because most of the vulnerable parts of a petrol engine such as cam belts and alternators have been designed out of the system.
Many of the problems reported and diagnosed as mechanical failure especially with the transmission has been misdiagnosed. The fault usually lie in a serviceable part such as spark plugs! It is important that you get a competent technician to diagnosed your vehicle as you could incur unnecessary repair bills.
Many Toyota Priuses have clocked up over 500,000 Kms on the same engine and are still operating perfectly.
Toyota Estima Hybrid
Unlike the Prius the Estima Hybrid have mechanical failure issues. This is because the design of the Estima Hybrid is different from that of the Prius. In the Estima Hybrid a 18Kw electric motor is coupled with a 2400 cc engine for the front wheel drive and a 17Kw electric motor drives the rear wheels to make it a 4 wheel drive arrangement.
The weakness lies in the combination of the 18 Kw electric motor with the 2400 cc engine. All is well when the hybrid battery is strong and can provide enough power to the electric motor. However when the battery weakens with age and can no longer hold an adequate voltage under load, high impact forces from the powerful engine can wreck the CVT band and transmission gears. Higher current will flow to the inverter which results in overheating of the 3 phase switching system causing inverter failures.
This is not to say that the Estima hybrid is not a good vehicle. I have seen a 2006 Estima hybrid that have clocked up 600,000 kms. The point is that the hybrid battery has to be in good working condition.
If you own an Estima Hybrid you need to install a Power Jockey. This holds up the operating voltage of the hybrid battery which will help in preventing the mechanical failures seen above.
Preventing mechanical failure in the first place.
A good servicing schedule is your insurance against expensive mechanical repairs. This especially includes getting your vehicle inspected by competent technicians and ensuring that serviceable items such as spark plugs, MAF sensors, and oxygen sensors are changed if not functioning correctly.
Cost of Repair
One issue that stands out is that hybrid owners are often quoted astronomical amounts for repairs often for repairs that are misdiagnosed. Be on your guard. Question their analysis and get a second opinion if you are not convinced. Some examples of our charges are listed below.
1) Standard service : On top of the normal spark plugs, filters and fluids checks, the service must include removal and full cleaning of the throttle body and scan testing MAF and Oxygen sensors. We charge $150 for this service.
2) Replacing MAF sensors: Depending on the cost of sourcing the new replacement,This operation can cost up to $800. We charge $300.
3) Replacing Oxygen sensors : Official cost of the O2 sensor can cost $400 so the replacement can cost $500 each. We have tested modified generic O2 sensors and found that they can be used to replace the original. Our charge is $200 each installed.
4) Sometimes cleaning the sensors in an ultrasonic bath can fix problem of dirty sensors.
5) Replace transmission : If this is necessary a used replacement is the most viable and should cost around $2500. In the Estima replacing the CVT band is possible and cheaper if available. Problem is that this band is not usually available as a spare part. Sometimes a noise that comes from the transmission system is actually due to faulty ignition systems in the spark plugs and coils or even a faulty inverter.
6) Change Inverter : New this item can cost up to $4000. A used replacement should set you back about $2000.
Other than the above there is not much that go wrong with Toyota hybrids, even though the vehicle may have done over 200,000 Kms.
