Why don't used natural gas or propane for fuel

If and industrial lift truck (forklift) can run in a virtual sealed building and no one gets carbon monoxide poisoning using natural gas or propane. GM builds direct inject natural gas or propane engines for yale forklifts; why can't Ford build them for cars as an alternative fuel instead of biofuels. The direct inject natural gas or propane engines have the same power and performance as gasoline engines but with the pollution. The direct inject natural gas or propane engines would not need emission control systems. Everybody needs to build more efficient engines like the honda did with first honda civic in 1973.
Matt 10/09/2012
I understand that Europe is moving away from the diesel engines, but I would welcome a 4 cylinder diesel if the engine were designed and built as a diesel engine and not converted from a gasoline engine.
David G 09/28/2012
i think you need to stop by your Ford dealer or at least visit the Ford website more (which doesn't always have the same info as the dealers), plenty of Fords were and still offered with "LPG." from the factory. True, some had to be fleet ordered. But the Crown vic for YEARS offered Propane (i.e."LPG") many of the Ford pick ups offer LPG, and I even remember used to seeing the Focus with the little blue "LPG" sticker in the bottom right.

And if a car you want isn't offered in LPG, its easy enough to convert a car to LPG!

What I would like to see more is more Diesel engined vehicles in north America/US. If they offer them in Europe, why not here? The emission standards can't be too different.

As far as LPG or Diesel, it seems US car co.s have somewhat committed themselves to hybrid!