View Single Post
Old 09-24-2014, 08:13 AM   #145 (permalink)
oldtamiyaphile
Master EcoModder
 
oldtamiyaphile's Avatar
 
Join Date: May 2009
Location: Australia
Posts: 1,510

UFI - '12 Fiat 500 Twinair
Team Turbocharged!
90 day: 40.3 mpg (US)

Jeep - '05 Jeep Wrangler Renegade
90 day: 18.09 mpg (US)

R32 - '89 Nissan Skyline

STiG - '16 Renault Trafic 140dCi Energy
90 day: 30.12 mpg (US)

Prius - '05 Toyota Prius
Team Toyota
90 day: 50.25 mpg (US)

Premodded - '49 Ford Freighter
90 day: 13.48 mpg (US)

F-117 - '10 Proton Arena GLSi
Pickups
Mitsubishi
90 day: 37.82 mpg (US)

Ralica - '85 Toyota Celica ST
90 day: 25.23 mpg (US)

Sx4 - '07 Suzuki Sx4
90 day: 32.21 mpg (US)

F-117 (2) - '03 Citroen Xsara VTS
90 day: 30.06 mpg (US)
Thanks: 325
Thanked 452 Times in 319 Posts
Quote:
Originally Posted by paulgato View Post
what is the issue with the turbo? Can I not simply kill the fuel injector pump? What is the difference between that and keying off and on again? (...other than wear and tear on the ignition switch of course.)
As mentioned above, the turbo can fail if it's not allowed to cool prior to the engine being switched off. The usual recommendation is to let the turbo cool for 30 seconds after a high boost event before switching off. TDI's are on boost at normal drive speeds much more so than petrol turbos typically would be (although modern low pressure petrol turbos share a similar duty cycle). In short you can't P&G (EOC) a TDI like you can a petrol, because it's high load/ boost then engine off. Diesels use so much less fuel at idle that petrols that the EOC advantage isn't that great. Ever wonder why few if any turbo diesel hybrids exist? Potential economy would be astronomical, but an exhaust driven turbo wouldn't last.

Ideally, I'd love to swap my T5's exhaust driven turbo for an electric supercharger someday, then I could add a 4motion rear axle with electric motor and I'd have the best of everything, 900Nm of torque combined, 4wd and 60MPG

DFCO in a diesel means a lot of air is being drawn in with no heat being added, a great way to cool your turbo prior to shut down.

As for wiring the kill switch to the PD pump, I'm not sure, my 2007 pump is still mechanical. I think for the relatively occasional EOC opportunities with a TDI, a kill switch is a low priority.
__________________






  Reply With Quote