air filter vs fuel economy - controlled test results
air filter vs fuel economy - controlled test results
(OP)
regarding thread71-214125: air filter vs fuel economy (tricky question?)
A government study has (FINALLY) shown that what they've been saying about filters and fuel economy has been wrong for 20 years, if it was ever right.
http://ww w.fuelecon omy.gov/fe g/pdfs/Air _Filter_Ef fects_02_2 6_2009.pdf
"Results show that clogging the air filter has no significant effect on the fuel economy of the newer vehicles (all fuel injected with closed-loop control and one equipped with MDS). The engine control systems were able to maintain the desired AFR regardless of intake restrictions, and therefore fuel consumption was not increased. The carbureted engine did show a decrease in fuel economy with increasing restriction. However, the level of restriction required to cause a substantial (10–15%) decrease in fuel economy (such as that cited in the literature3,4) was so severe that the vehicle was almost undrivable. Acceleration performance on all vehicles was improved with a clean air filter."
A government study has (FINALLY) shown that what they've been saying about filters and fuel economy has been wrong for 20 years, if it was ever right.
http://ww
"Results show that clogging the air filter has no significant effect on the fuel economy of the newer vehicles (all fuel injected with closed-loop control and one equipped with MDS). The engine control systems were able to maintain the desired AFR regardless of intake restrictions, and therefore fuel consumption was not increased. The carbureted engine did show a decrease in fuel economy with increasing restriction. However, the level of restriction required to cause a substantial (10–15%) decrease in fuel economy (such as that cited in the literature3,4) was so severe that the vehicle was almost undrivable. Acceleration performance on all vehicles was improved with a clean air filter."





RE: air filter vs fuel economy - controlled test results
- Steve
RE: air filter vs fuel economy - controlled test results
rmw
RE: air filter vs fuel economy - controlled test results
@rmw - dream on. :)
RE: air filter vs fuel economy - controlled test results
RE: air filter vs fuel economy - controlled test results
- Steve
RE: air filter vs fuel economy - controlled test results
RE: air filter vs fuel economy - controlled test results
When will it all end?
RE: air filter vs fuel economy - controlled test results
I've lost faith completely with the TV auto folk. I now only watch for the high jinks (which I really, really enjoy).
- Steve
RE: air filter vs fuel economy - controlled test results
RE: air filter vs fuel economy - controlled test results
RE: air filter vs fuel economy - controlled test results
RE: air filter vs fuel economy - controlled test results
RE: air filter vs fuel economy - controlled test results
My '99 Mitsubishi Magna (Diamante) improved its fuel economy by about 20% after a filter change.
Filter was at least 5 years old. It was not obviously very dirty. The car was certainly not 'almost undrivable' before the change.
Fuel consumption figures were read off the On Board Computer display.
RE: air filter vs fuel economy - controlled test results
RE: air filter vs fuel economy - controlled test results
Perhaps the polishing of the on board crystals did it.
RE: air filter vs fuel economy - controlled test results
During this whole episode, mileage did not change whatsoever; my logs from the period before I discovered the nest showed no change from the previous year, and no change after I changed the filter.
Only thing noticeable was a reduction in available power, mainly passing other vehicles...
RE: air filter vs fuel economy - controlled test results
If it was FI, something else was at work, whether it be manner of use, or other things changed with the service or a spontaneous change in calibration of the on board computer or the crystals, either the laws of physics changed or something beyond your observation or knowledge changed.
Maybe we might drop into your specialised areas and start supporting obviously wrong in fact folk law, just to test the consistency in attitude.
Regards
Pat
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RE: air filter vs fuel economy - controlled test results
I don't see any need to be snippy; it is observations like his that undoubtedly drove the gov't to sponsor the test.
I also suspect there will be FTC (Federal Trade Commission) challenges to any claims made for mileage improvements in parts/service ads from now on.
RE: air filter vs fuel economy - controlled test results
This guy out of hand disputes those findings and the findings of the government funded project, then admits he doesn't really have any expertise, then makes a snide remark about polished crystals when challenged.
What part of that scenario does not invite a rebuff or a red flag. I chose a rebuff as opposed to a flag in the hope he might pull his head in and the thread would stay intact.
The inference re false advertising was broached in the previous thread, though from memory it was broached with no geographic inference.
Regards
Pat
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RE: air filter vs fuel economy - controlled test results
- Steve
RE: air filter vs fuel economy - controlled test results
RE: air filter vs fuel economy - controlled test results
RE: air filter vs fuel economy - controlled test results
Thanks Pat, your suggestion is noted, but rejected.
RE: air filter vs fuel economy - controlled test results
Regards
Pat
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