We catch up with our technical chaps to see if they have any thoughts about driving in the current snow and ice….. and here’s what they said!
Auto Transmissions:- Some have a Snow button function, in short the Autobox ECU forces the box to shift-up to a higher gear and will not allow a low gear like 1st or second to be selected when the “Snow Button” is pressed. The philosophy being that if you gradually move off by tickling the throttle in a high gear there will be less chance of wheel spinning and losing traction, more importantly you will begin to move forward slowly and safely.
ESP:- If your transmission does not have this function or you may have a manual transmission the “Traction Control” function of your ABS/ESP should kick in. What is this then………………modern vehicles have a number of ways of providing you with traction control “Wheel spin prevention in low traction conditions” How do you know it’s working, when traction control kicks in the ESP light will flash on the dash board, you can press the throttle as hard as you want the system reduces engine power. There are many ways by which the transmission, ABS and engine ECU’s prevent wheel spin, the most common are:- Cutting the fuel delivery to the injectors, ABS braking the wheels or a combination of these in very quick succession.
Diesel engines:- Modern HDI (High Pressure Direct injection) still have heater plugs but rarely use them due to their high combustion efficiency and ability to start in cold conditions. In recent years manufacturers have removed the heater plug light from the dash board therefore in very cold conditions like we are currently experiencing you will need the heater plugs but will not necessarily have an indication on the dashboard of their run or heat duration. Advice is with HDi engines in very cold weather switch on ignition for a few seconds before cranking the engine to allow heater plugs to run a cycle.
Old Diesel engines Direct or Indirect injection:- Will all have heater plugs and a dash light to indicate their run cycle, when the weather is very cold let them run for three cycles, i.e switch on ignition, let the plugs run a cycle, watch light on dash go out then repeat another two times. Do not use ether type sprays into the induction system, they wash critical oil off the piston rings for first time start and rapidly increase cylinder bore wear. This is like pouring salt in wound, the engine is already a poor starter due to piston ring & bore wear, diesel engines rely on the heat generated on the compression stroke to start. Spraying these ether aid starters into the induction system accelerates the wear process, which is why motorists say that an old diesel engine becomes addicted to these ether spray starting aids.