Seems these days cars are begining to be ever more complicated. Unfortunately the government are not helping. The introduction of a diesel particle filter on the majority of diesel cars in 2006 was hailed by the government as a great way to cut C02 emissions. The idea was to have a capture chanber with a "carbon cake" to absorb soot from the engine exhaust gas. Once this "cake" was sufficiantly full then the engine would inject extra diesel to heat up the filter to 800 degrees c and burn the soot off. Apparently this is cleaner than just expelling it in the first place. Problem is that if you dont drive at least constantly for 15 mins per week the DPF doesnt have chance to heat, therefore with the extra help is still not hot enough to regenerate. Soot builds up and up and eventually the DPF becomes blocked. Manual regens can be done at cadillac dealerships using tech 2 but this will cost you. So how can you ensure your filter is free flowing? Well follow the points below:
1. Always go on a long run once a week. I would suggest 30 mins rather than 15. It takes 15 mins for the cycle to complete.
2. On your long run keep the car at 2500-3000 rpm, this may mean driving in 4th or 5th. This will allow for optimum temp.
3. At junctions on any trip pull away hard once in 2nd gear or 3rd. If you look in the wing mirror you will see either a plume of black or trail of black soot. This stops the soot accumulating in vast quantities on the DPF cake.
4. If the regen process has started, dont stop the car, continue driving even if this means doubling back on yourself before getting to your destination. This will ensure the process completes and no stray unburnt diesel ends up in your sump.
All in all the DPF is a major pain to the diesel driver and is counter productive as you have to drive the car at high revs and for long trips just to stop the filter clogging. This not only increases fuel consumption but also emissions. For some DPF horror stories affescting all manufacturers google DPF problems. Or look at this unluck guys post:
http://www.honestjohn.co.uk/forum/post/index.htm?t=70841
1. Always go on a long run once a week. I would suggest 30 mins rather than 15. It takes 15 mins for the cycle to complete.
2. On your long run keep the car at 2500-3000 rpm, this may mean driving in 4th or 5th. This will allow for optimum temp.
3. At junctions on any trip pull away hard once in 2nd gear or 3rd. If you look in the wing mirror you will see either a plume of black or trail of black soot. This stops the soot accumulating in vast quantities on the DPF cake.
4. If the regen process has started, dont stop the car, continue driving even if this means doubling back on yourself before getting to your destination. This will ensure the process completes and no stray unburnt diesel ends up in your sump.
All in all the DPF is a major pain to the diesel driver and is counter productive as you have to drive the car at high revs and for long trips just to stop the filter clogging. This not only increases fuel consumption but also emissions. For some DPF horror stories affescting all manufacturers google DPF problems. Or look at this unluck guys post:
http://www.honestjohn.co.uk/forum/post/index.htm?t=70841