More manufacturers are going the direct injection petrol route. VAG, Porsche, Mitsubishi, BMW, Mercedes Benz to name a few, with most of the others exploring the technology.
Given that early examples of the VW FSI and Ford SCi have a pretty terrible reputation for longevity and reliability, and even PSA abandoned their first Di engine on reliability grounds, has this technology now improved to the point where it's a sensible long term ownership proposition? Or were the problems overstated in the first place?
This isn't a precursor to a buying decision, I'm just curious. On paper, these engines do seem to make a significant dent in diesel's running cost advantage, without the noise and truncated rev range compromises of even a good diesel engine.
Cheers
DP
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I can only hope so - I'm planning to run the 2.3 DISI in my Mazda 3 MPS to a high mileage. It was one of the first turbo petrols with direct injection, so I have no doubt similar designs have progressed a bit over the last few years.
Other than always having sounded slightly dieselly on start-up, there's nothing to give the DI away and it's been faultless so far (35k miles). Economy consistently 3-4 mpg better than I would expect of a non-DI 4-pot petrol of the same output (28 mpg, and by no means babied). The benefits should be greater still in something less performance orientated.
Weren't some of the FSI issues related to fuelling? Mine gets nothing but 99RON V-Power, and has sensible 9k oil change intervals, so here's hoping it will prove robust.
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>Weren't some of the FSI issues related to fuelling? Mine gets nothing but 99RON V-Power, >and has sensible 9k oil change intervals, so here's hoping it will prove robust.
Why buy a car for high milages that needs far more expensive fuel when you can get ordinary engines with performance and longevity as good but not the expense?
Edited by Altea Ego on 03/03/2009 at 17:23
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> Why buy a car for high milages that needs far more expensive fuel when you can get > ordinary engines with performance and longevity as good but not the expense?
I don't know any high output turbos that I'd be happy to run on 95RON, regardless of whether they were direct injection or not. The difference in running costs over my average 10-12k annual miles is negligble in any case.
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Didn't Mitsubishi make a DI petrol engine for the Galant model?
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I was going to say the Vauxhall 2.2 Direct engines have been a great success, but then I remembered the fuel pump/regulator issues...
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I owned a Mitsubishi GDI which went through 2 replcements sets of injectors in 2 years and needed de-cokeing(dealer term) every service.
Carse.
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Injecting fuel into a cylinder which is under compression needs very high pressures in order to ensure proper atomisation and acceptable timing and fuel metering. The nozzles and pressurising pump(s) have to be made to a very high degree of precision in order to achieve this.
Diesel fuel is a lubricant, petrol is a solvent with no lubrication qualities whatever.
My belief is that a direct injection petrol fuel system has no long term prospects - so far nobody has produced a reliable one.
659.
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The FSI injector issue was due to the level of Sulphur in the fuel - at the time they were first introduced to the UK market, UK petrol had significantly more sulphur content than continental petrol. As high octane fuel had lower sulphur content that meant it became the recommended option. The recent FSI engines no longer recommend high octane fuel as the level has now been dropped to under 10ppm across Europe.
I see no issues with the FSI technology and have had no problems with my engine in the first 20k and see don't expect any to develop in the next 20k or further.
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It worked well at the beginning of WW2 The German 109 had superior aerobatic engine performance over the carbureter fed Merlins in the Spitfires and Hurricanes until a mod known as pennies washer in the carb kept them running at full power in extreme attitudes.
Should have improved since then?.
ndbw
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I understood the UK carburettor mod was known as "Miss Shilling's Orifice"...
www.enginehistory.org/Reviews/book_reviews_4.htm
last one.
Edited by Another John H on 03/03/2009 at 20:11
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It worked well at the beginning of WW2 The German 109 had superior aerobatic engine performance over the carbureter fed Merlins in the Spitfires and Hurricanes until a mod known as pennies washer in the carb kept them running at full power in extreme attitudes. Should have improved since then?.
your close ndbw, it was actually called miss shillings oriface.. named after tilly shilling who came up with the idea of fitting a small metal disc in the carb to stop back flow and causing fuel stavation in the merlin engines in spitfires when pulling negative Gforces
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Fascinating information on the redoubtable Mrs Shilling- I'd never heard of her and am grateful for these posts. A credit to this forum!
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I think they used to say penny washer. We did not talk about orifices and ladies in those days.
ndbw
Edited by rtj70 on 04/03/2009 at 17:47
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It worked well at the beginning of WW2 The German 109 had superior aerobatic engine performance over the carbureter fed Merlins in the Spitfires and Hurricanes
But suprisingly the merlin produced more horsepower with less cubic capacity.
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Before this thread gets locked for going off topic, I would like to recommend the book ?Not much of an engineer? by Sir Stanley Hooker; a great read and full of interesting facts about Merlin and other British aero engines, by the man who was there.
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>>?Not much of an engineer?
Seconded - it's an excellent book.
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I had an early model Mk V golf with the 1.4 FSI unit, which drank oil for fun. Several visits to several different VW garages (ranging from Sheffield to Ipswich, via Nottingham) all drew the same response........characteristic of the engine sir, nothing to worry about. Apart fromt the £14 per litre Castrol GTX it needed every 1500 miles.....
Never again.
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Sounds like I'll stick with diesel for my next car choice!
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If you heard our Zafira 2.2 direct at idle you'd swear it was a diesel... ;)
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So in the near future the choice will be between forced induction direct injection petrol or forced induction diesel with DPF.... what a choice.
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