Warming Up: P&G? PEOG? Steady Throttle? - Fuelly Forums

Click here to see important news regarding the aCar App

Reply
 
Thread Tools Display Modes
 
Old 12-15-2008, 11:54 AM   #1
Registered Member
 
aalb1's Avatar
 
Join Date: Apr 2007
Posts: 207
Country: United States
Warming Up: P&G? PEOG? Steady Throttle?

So pulling out of the driveway on these cold mornings got me thinking...

"What driving style is best for FE in the cold? P&G? P&EOG (Pulse & Engine-Off Glide)? Steady Throttle?"

I drive a Honda Civic and it seems that it takes longer to get to Operating Temperature than other cars. My Wife's Jeep and friend's Lexus takes much quicker to get to operating temp.

So while running rich on these cold mornings is P&EOG still the most effective hypermiling technique? Or is it better to get to operating temps quicker with P&G or steady throttle?
__________________

__________________
aalb1 is offline   Reply With Quote
Old 12-15-2008, 12:10 PM   #2
Registered Member
 
Join Date: Nov 2007
Posts: 1,111
Country: United States
Send a message via AIM to dkjones96
There are a few reasons for reduced fuel economy when the engine is cold. One of them is that the engine parts have contracted as they've cooled and you end up with increased blow-by and relatively loose clearances.

Because of this, I would personally recommend steady state. Most of the time I don't force the engine to pull further than the torque peak as long as the temp gauge is still buried in the cold.
__________________

__________________
- Kyle
dkjones96 is offline   Reply With Quote
Old 12-15-2008, 01:44 PM   #3
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
Nice job on the term PEOG. I haven't seen it before, but it's every bit as good as my idea of calling it P&EOC. No matter what, it's good to differentiate between engine-on P&G and engine-off P&G.

I think the lower temperature doesn't change what is the most fuel-efficient strategy, but it does bring other concerns such as warm-up, increased clearance as mentioned above, etc. Looking at FE only, whatever was best before is probably still going to be best.

My VW takes forever to warm up no matter what, although I suppose I could flog the hell out of it and warm it up faster. With reasonable driving, whether hypermiling or driving like everyone else, full grille block or none, it won't warm up until I get on the highway 7 miles (15 minutes) down the road...usually a mile on the highway before heat is useful.
__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 12-15-2008, 11:00 PM   #4
Senior Member
 
Join Date: Aug 2008
Posts: 114
Country: United States
It's -15. I let it idle 7-10 minutes, otherwise my breath frosts the window over faster than it takes to warm up enough to keep clear. I need more blockage, as even when its warm its only 175, far too cold right now. I usually drive a steady rate, keeping it around 2000rpms. I also use a large vinyl fabric--soft on one side, vinyl on the other--to keep external frost off the windshield. A nice by product is all the heat that flows out of the hood vents is it stays on the window, decreasing warm-up times slightly, and allows me to drive sooner since the window is clear.
almightybmw is offline   Reply With Quote
Old 12-16-2008, 05:02 AM   #5
Registered Member
 
Join Date: Sep 2005
Posts: 262
Country: United States
The 7-10 minutes of idling must be great on gas...

If you get a 30 dollar block heater, and plug it 2 hours before you use your car, u will be able to start driving it right of the bat. Get a timer if its morning use, but idling is the less FE thing u can do, also its not ecological at all.
GasSavers_BIBI is offline   Reply With Quote
Old 12-16-2008, 06:21 AM   #6
Registered Member
 
palemelanesian's Avatar
 
Join Date: Apr 2013
Posts: 364
Country: United States
P&EOC or whatever you call it is the best strategy for fuel usage. If you want heat, it's the worst strategy. Take your pick - low fuel or warm engine. Any driving style that warms it up faster also burns more fuel, and it will NOT be recovered by better mileage later. I've tested this.
palemelanesian is offline   Reply With Quote
Old 12-16-2008, 06:31 AM   #7
Registered Member
 
GasSavers_RoadWarrior's Avatar
 
Join Date: Feb 2008
Posts: 1,652
I'd take a look at the thermostat if it's taking that long to get warmish, possibly stuck open, or not fully closing.

I found 0W30 oil helps a lot in winter, I have only 4 blocks to drive before hitting the highway on ramp. With regular oil in cold weather, the car is still very sluggish and it feels "bad for it" in accelerating up to highway speed before the oil is fully warm and it's in closed loop. With 0W30, it feels good within 30 seconds or 1 block.
__________________
I remember The RoadWarrior..To understand who he was, you have to go back to another time..the world was powered by the black fuel & the desert sprouted great cities..Gone now, swept away..two mighty warrior tribes went to war & touched off a blaze which engulfed them all. Without fuel, they were nothing..thundering machines sputtered & stopped..Only those mobile enough to scavenge, brutal enough to pillage would survive. The gangs took over the highways, ready to wage war for a tank of juice
GasSavers_RoadWarrior is offline   Reply With Quote
Old 12-16-2008, 06:41 AM   #8
Registered Member
 
aalb1's Avatar
 
Join Date: Apr 2007
Posts: 207
Country: United States
Quote:
Originally Posted by RoadWarrior View Post
I'd take a look at the thermostat if it's taking that long to get warmish, possibly stuck open, or not fully closing.
Who are you talking to here? Honda's take notoriously long to warm up. But my friend's lexus takes about 1.5 minutes. I'm simply amazed at the difference.
__________________
aalb1 is offline   Reply With Quote
Old 12-16-2008, 06:44 AM   #9
Registered Member
 
aalb1's Avatar
 
Join Date: Apr 2007
Posts: 207
Country: United States
Quote:
Originally Posted by PaleMelanesian View Post
P&EOC or whatever you call it is the best strategy for fuel usage. If you want heat, it's the worst strategy. Take your pick - low fuel or warm engine. Any driving style that warms it up faster also burns more fuel, and it will NOT be recovered by better mileage later. I've tested this.
Sounds like thinsulate it is!!!
__________________
aalb1 is offline   Reply With Quote
Old 12-16-2008, 07:38 AM   #10
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
Quote:
Originally Posted by BIBI View Post
If you get a 30 dollar block heater
I had no idea they were so cheap. I'll be looking for one now...
__________________

__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
New graphic idea MatrixDom Fuelly Web Support and Community News 2 03-11-2012 12:17 PM
Landspeeds E-bike Conversion (Mk2) landspeed People Powered 5 06-06-2008 07:37 PM
94 Accord manual trans swap- which trans has the tallest gears? GasSavers_Erik General Maintenance and Repair 2 05-25-2008 07:01 AM
Hey Rabby Introduce Yourself - New member Welcome 1 05-21-2008 10:15 AM
Tire Width bowtieguy General Maintenance and Repair 4 04-02-2008 04:41 PM

» Fuelly iOS Apps
Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 11:08 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.