I had just returned from a trip to the Kruger National Park when I noticed white smoke pouring out of the exhaust of my 2015 Toyota Fortuner D4-D (5 000 km on the odo) when I accelerated onto the N4 for the first time after dawdling about in second or third gear for the duration of our stay. The white smoke disappeared after about 30 seconds. Upon inspection, I found all fluid levels were normal.
On my way home I watched for signs of white smoke on downhills after running against compression for a while and when accelerating uphill, but I didn’t see anything. Is it oil smoke, raw diesel in the exhaust or where does it come from? As far as I know this vehicle is not fitted with a diesel particle filter (DPF) where extra diesel is injected into the exhaust system to clean the DPF. Should I be concerned?
MARIUS GRUINDELINGH
Newcastle
Answer: Normally white smoke points to raw diesel in the exhaust, but we doubt that is the case with your new Fortuner. Besides, you would have seen continuous clouds of white smoke with a leaking injector. The other possibility is water in the exhaust owing to a leaking head gasket, but again that’s more likely to happen in the case of an older vehicle.
Perhaps owing to all the low-speed driving you did, water vapour condensed somewhere in the exhaust system (remember, the exhaust-gas temperature of a diesel engine is much lower than that of a petrol engine and the gas-flow rates at low loads are minimal).
The first time you increased the engine load, resulting in higher exhaust temperatures and increased gas-flow rate, the water evaporated and the vapour was blown out of the exhaust in the white cloud you spotted.
