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Ask the Mechanic: Why does my car slow down or stop when the engine is running?

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Hello Paul, I drive a Honda CRV 2015 but after driving for about one to two hours, the vehicle slows down and stops. The engine will still be running but the car will not move no matter how much I accelerate. What could be the fault?


Hello James, your Honda CRV seems to slow down or outright stop, even when you accelerate it fully when you drive it for two hours or a little while. The two common causes of this are a failing automatic transmission or jamming brakes. First, get a mechanic to check the condition of the transmission fluid in case it is overdue for service or dirty.

Aged transmission oil will degrade and lose its ability to cool down transmission components. Its viscosity or ability to flow easily is reduced or it becomes too light to protect against frictional damage or the hydraulic function, which helps the automatic gearbox to engage gears. A computer diagnosis can help you establish whether there is electrical or mechanical damage in the automatic gearbox.

Should the gearbox and oil be okay, check the brakes to rule out jamming callipers. A faulty automatic gearbox or jamming brakes can cause the car to slow down or stop, even when the engine is running or revving up.


Hello Paul, I have a Nissan Elgrand model 1997. I have tried to drive it up to 180 kph but when it reaches 170, it drops back. Why?


Hello Israel, your car comes factory-fitted with a speed limiter, which is preset to lock your top speed at 177 kilometres per hour (approximately 110 MPH). The speed limiter facility is programmed with your engine control module to prevent you from exceeding what is considered a safe speed by Japanese Domestic market regulations.

Speed limiter systems are often used by fleet owners to regulate the speed of their drivers. This is intended to enhance road safety as well as reduce traffic fines picked up by speeding drivers. Fleet owners are also concerned about the increasing fuel and repair costs arising from speeding and accidents. Using the in-built speed limiter made the Elegrand an attractive choice for buyers back in 1997.


Hello Paul, I would like your help in identifying the key security features of a genuine motor vehicle logbook. Also, are Toyota Probox spares easy to find?


Hello Johnson, the current online generated logbook does not have as many physical security features such as watermarks, holograms and security seals, which were found on the older thick manila-type logbooks. However, the new online generated genuine log books have bar codes and QR codes that can be scanned to reveal the correct details of the vehicle and its owner. This seems to be more secure and convenient. Besides you can go online and verify the details on the logbook with Uganda Revenue Authority.

The Toyota Probox is a very popular car because of its practicality and flexibility as a cargo and people mover, excellent features for small businesses. This makes spare parts readily available and affordable.

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