On 25 May 2004 at 15:32, Falcon Wireless Tech Support wrote: > ----- From: "Bob Japundza" > > I have a friend that just bought a 2004 GMC 2500 diesel pickup. The > engine controller uses a 32-bit microprocessor, and they use that as a > selling point. When I first heard that I thought man, throwing a > spark and a squirt of fuel in a cylinder is getting more complex > nowadays. I'm sure that the new 2005 emissions regulations in the US > have something to do with that. > > Regards, > Bob > > Actually, you seem to be overlooking the fact that a DIESEL engine > does not even require a spark. To the best of my knowledge even the > "squirt of fuel" is a mechanical function carried out by the diesel > injection pump, the timing of which must be at an exact point in the > pistons compression stroke. So basically the on-board computer has > little to do with running the engine on a diesel. > > $.02KF4HAZ - Lonnie > I understand some new diesels are "direct inject", which means they use electro-mechanical injectors to squirt the diesel directly into the cylinder. The timing then becomes just as critical as it is with a spark ignited petrol engine. The fuel metering is obviously just as important too, so the ECU would have pretty much the same amount of work to do as in a petrol engine. $0.02 (times 0.62 for current exchange rate ;-)) Brent -- Brent Brown, Electronic Design Solutions 16 English Street, Hamilton, New Zealand Ph/fax: +64 7 849 0069 Mobile/txt: 025 334 069 eMail: brent.brown@clear.net.nz -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu