Hybrid Car – More Fun with Less Gas

70 mpg - Page 20

register ::  Login Password  :: Lost Password?
Posted by Michael B on January 7, 2010, 12:33 am
 


No, but I'll bet a vacuum gauge could.
I got the Scan Gauge because of an erratic
"check engine" light that the dealership said
was a glitch that could be ignored. Next time
it shows up, I'll need to check for that error code
and decide if it needs to be reset.

On Jan 5, 9:22pm, m...@privacy.net wrote:



Posted by news on January 5, 2010, 12:02 am
 


On Mon, 04 Jan 2010 13:22:51 -0700, wmbjkREMOVE@citlink.net wrote:


I have an OBDII reader ($8US) and some PC software (both free and
paid) that I use on an old laptop.  The biggest value to me is knowing
what conditions affect mileage and how best to manually shift the
automatic transmission - the OEM computer is relatively stupid and
very slow to respond - as in waiting so long to downshift on a long
grade that it must go down two gears instead of one.  Waiting that
long to down shift means the engine is kicked up to 5500RPM to
maintain highway speed which is not fuel efficient - nor is it
particularly kind to the engine.  A manual downshift from 4 to 3 when
the engine load increases audibly works fine.  

I'm considering building a downshift unit that does the 4->3 shift
(solenoid to kick the shift lever to the side) when road speed is
above 50mph and the engine load increases by 10% or so.  When engine
load decreases for more than 60 seconds, a solenoid on the other side
would kick the shift lever back to drive.  I'm confident that my
design can respond within a second or so, instead of the 5 seconds the
OEM computer requires.
 
The transmission lockup at lower speeds only releases when the road
speed drops to somewhere near 20MPH, so you wind up braking against
the engine's momentum (remember that the return to idle speedl is
computer controlled to reduce pollution - it doesn't happen
immediately when you take your foot off the gas pedal).  Hitting the
brakes *should* release the lockup mechanism at speeds below 35MPH.

John


Posted by Michael B on January 5, 2010, 12:24 am
 

But how about causing it to kick out completely and
freewheel down a hill? Or at a stop?

On Jan 4, 7:02pm, n...@jecarter.us wrote:



Posted by news on January 5, 2010, 6:30 pm
 

On Mon, 4 Jan 2010 16:24:43 -0800 (PST), Michael B


While possible, I choose to not have a semi-autonomous device putting
the transmission in neutral.  An unexpected 4->3 or 3->4 shift might
be disconcerting to another driver, but does not require any action on
the driver's part to maintain driveability.  With a neutral coast
option on downgrades, some drivers would stay on the brakes
continuously on a long downgrade, leading to loss of braking from
overheating.

(Have you ever driven the western route through Virginia and North
Carolina?  There are sections of road with 4 runaway truck ramps on a
single long downhill segment.)

John



Posted by Michael B on January 4, 2010, 11:22 pm
 

Reason I mentioned getting it at Auto-Zone was because
it's the Scan-Gauge 2. And I had to give them its stock
number, because the staff didn't even know about it.

I mainly watched instantaneous MPG while I learned
the quirks of my "new" Saturn Ion 5 speed. The neatest
part was in letting off an incredibly small amount on the
gas and seeing nearly 5 MPG improvement on the gauge.

No surprise, without jackrabbiting it's best to get out of
the lower gears, but there really needs to be a sixth gear.
But I knew that from during my days with a 64 VW Beetle.

On Jan 4, 1:44pm, m...@privacy.net wrote:


This Thread
Bookmark this thread:
 
 
 
 
 
 
  •  
  • Subject
  • Author
  • Date
---> Re: 70 mpg Jim Wilkins01-03-2010
| |--> Re: 70 mpg Jim Wilkins01-03-2010
| | `--> Re: 70 mpg Bruce Richmond01-16-2010
| |--> Re: 70 mpg Bruce Richmond01-17-2010
| |     ---> Re: 70 mpg Alistair Gunn01-19-2010
| |       `--> Re: 70 mpg Daniel who want...01-19-2010
| ---> Re: 70 mpg Bruce Richmond01-16-2010
please rate this thread