I want to congratulate you for this very useful column in Top Gear. I just would like to ask your help to spread the information on unnecessary prolonged engine warm-up.
We used to enjoy fresh air in our place until our neighbor bought a brand new AUV with diesel engine. Their driver used to drive a truck for a logging company. Their vehicle is more than five months old now and they have the habit or ritual of running the engine idle for ten minutes in their garage, which is about 30 meters from our home. The air becomes so bad it hurts your eyes and lungs every time the AUV's engine runs that long. I have told their driver about their practice but he still continues to do it. I hope you can help preserve our environment through your column.
Thanks and more power.
Thanks for your kind words.
Unfortunately, your neighbor's driver is misinformed about modern engines. Modern manufacturing methods applied since the early 1990s no longer require most engines a long amount of warm-up time. Any engine made after that time will automatically warm itself up upon startup (assuming it's a cold engine) at about 1500rpm and normalize to the typical idle rpm or about 750 to 900rpm. This happens automatically--assuming there is nothing wrong with the cold start mechanism of the vehicle.
Keeping your engine running for warming up purposes does nothing but unnecessarily pollute the environment, waste fuel and the car owner's money.
Too bad that most of the driver's on the road don't really get the proper know how in using and maintaining their vehicles. Such knowledge would surely help save quite a bit of fuel as well as dramatically lessen the unnecessary vehicle emissions into our environment.