I've been reading up on diesels and have learned about the 3 modern methods for direct injection. If someone know the pros and cons and/or other methods please join in.
1)Distributer pump- Has one pump and a valve that directs the fuel to each cylinder
2)Common rail- Has one super high pressure pump that supplys fuel to each cylinder all the time (I think?).
3) The last method is when each cylinder has its own pump.
3) The last method is when each cylinder has its own pump.
VWs PD ... PumpeDuse. Fuel is delivered to the filter at 14 psi, then is stepped up with a fuel pump to higher pressure and then cam driven at each cylinder to extreme pressure to 27,000+ psi for greater atomization of fuel as it is "pumped" into the cylinder. VW diesel after 2004 all have this system. (previous systems used a traditional fuel pump and 'pop' injectors that provided half the psi of the newer PD or your number 2 Common Rail system. (Common rail does indeed have a rail that is fully pressurized to max injections pressure)
Hi Lakedude,
Quite a good read HERE with regards to RichC's reply - a comparison between Common Rail and PD.
I am not so sure that this statement is true about the Common Rail system however; "combustion noise is reduced to almost petrol engine levels"
Well, it certainly doesn't apply to my Civic at tickover anyway...
I am yet to hear a quiet diesel at low RPM's - however I haven't had the opportunity to listen to the new i-CTDi unit in the Accord at close hand yet.
The new Toyota Avensis diesel (177bhp) is meant to be a good bit quieter than the petrol version - but how much of that is down to hiding all the clatter with extra sound insulation is anyone's guess!
Diesel tech.
Pretty quiet. It doesn't match a Japanese engineered 'gasser' for 'hush' ... but the CDI is amazingly quiet.
