meby
Veteran Member
Has anyone considered plugging in the block heater in the summer half an hour or an hour before leaving to eliminate cold starts? Would the savings overcome the cost of electric?
Newbies and Vets: Tips for better fuel economy!
- Thread starter BleachedBora
- Start date
NarfBLAST
Top Post Dawg
I'm thinking of installing a zerostart coolant heater for cold winters but maybe could use it in the summer too.meby said:
Considering a 1000watt unit it just depends how much electricity costs in your area. say 10 cents per kwh. lets splurge and run it for an hour...
At cold idle my Scangauge reads from .6 to 1.2 somewhere, lets call it 1.0L/hour. 1L of fuel costs 140 cents lately. so for 10 cents you get 1/14th of liter or you could run for 1/14th of an hour... multiply by 60 minutes thats 4.28 minutes.
So you could run the heater for half an hour to an hour or idle the car for two to four minutes for the same cost. But I would argue that using the elctric heater would get the engine much warmer than idling. Instead of idling that same ammount of fuel would get me aprox 15 to 30 seconds of driving at my average 5.0L/100km... that would not warm the engine that much either.
My conclusion is that it would definetly cost less to use the heater to bring the engine temperature up. But would the improvement in effecientcy be worth the trouble of plugging/unplugging you car? I think I would like to get used to plugging in my car daily for when they finally start selling plug in electric vehicles
Clarifying tip no 1: Run tire pressure at 90% of recommended max pressure as state
My tire have max pressure of 51 PSi as shown below.
Does your rule number one "1) Run tire pressure at 90% of recommended max pressure as stated on side of tire. ..." imply that I shold inflate my tires at 90% of 51 psi = 46psi?
46 psi seems pretty high.
Please confirm that this is correct.
tnx
..................
This all brings us to:
BB's tips for higher mileage*, in his order of easiness and cost effectiveness, and according to his own experience--he has multiple tanks in a row with over 60 MPG. He's also one of the very few members to get 900 miles in a tank WITH A MKIII (15 gallons). Driving for milege is hard to do unless you know what to do--again YMMV:
1) Run tire pressure at 90% of recommended max pressure as stated on side of tire. ........."
My tire have max pressure of 51 PSi as shown below.
Does your rule number one "1) Run tire pressure at 90% of recommended max pressure as stated on side of tire. ..." imply that I shold inflate my tires at 90% of 51 psi = 46psi?
46 psi seems pretty high.
Please confirm that this is correct.
tnx
..................
This all brings us to:
BB's tips for higher mileage*, in his order of easiness and cost effectiveness, and according to his own experience--he has multiple tanks in a row with over 60 MPG. He's also one of the very few members to get 900 miles in a tank WITH A MKIII (15 gallons). Driving for milege is hard to do unless you know what to do--again YMMV:
1) Run tire pressure at 90% of recommended max pressure as stated on side of tire. ........."
oysterengineer
Member
For ~3 decades, my habit has been to inflate tires to 110% of the sidewall pressure. I estimate this totals on-the-order of half a million miles of driving experience, or ~2 million tire miles of experience.tothemax said:My tire have max pressure of 51 PSi as shown below.
Does your rule number one "1) Run tire pressure at 90% of recommended max pressure as stated on side of tire. ..." imply that I shold inflate my tires at 90% of 51 psi = 46psi?
46 psi seems pretty high.
Please confirm that this is correct.
tnx
..................
This all brings us to:
BB's tips for higher mileage*, in his order of easiness and cost effectiveness, and according to his own experience--he has multiple tanks in a row with over 60 MPG. He's also one of the very few members to get 900 miles in a tank WITH A MKIII (15 gallons). Driving for milege is hard to do unless you know what to do--again YMMV:
1) Run tire pressure at 90% of recommended max pressure as stated on side of tire. ........."
My logic is that the sidewall pressure limit includes some margin for various driving conditions, the most challenging is high speed, hot weather conditions. I assume that the design hot weather condition must be something on-the-order of 120 deg F and the design high speed condition must be on-the-order of 80 mph. Since I don't drive high speed and Western Washington doesn't have hot weather (the highest recorded temperature ever recorded in Olympia is 105 deg F), it seems reasonable to consume some of the tire's margin for the benefit of better mileage. And, my experience appears to show it is a reasonable choice.
Most pickup truck tires have sidewall limits of 70 to 80 psi, so 56 psi seems low.
Thank you for your input
Thank you for your input
i will give it a try and use 90% of max (51 psi) on my 03 jetta and inflate to 45 psi.
it does get pretty hot here in Nor Cal. we have had up to 113 F a couple weeks ago.
P
Thank you for your input
i will give it a try and use 90% of max (51 psi) on my 03 jetta and inflate to 45 psi.
it does get pretty hot here in Nor Cal. we have had up to 113 F a couple weeks ago.
P
oysterengineer said:
pjtremont
Member
the importance of "gap distance"
Much of the guidance I have seen on increasing mpg is helpful, but leaves out something that has made a big difference in my mpg numbers-- accepted gap distance (space between you and the leading vehicle).
On interstates I try to leave 8 or so times my speed in feet (roughly). So at 60, I try for 480 feet or so. Then as soon as the lead vehicle brakes, shift to neutral and if necessary roll right up to the lead vehicle. Most of the time you will be able to accelerate again well before getting within 5 feet of the lead vehicle and you'll never touch the brakes.
If you have the extra time and patience for this kind of driving, the payoff can be exceptional. I also have taken the following steps to reduce fuel consumption in my '02 Golf TDI (with, btw, 157,000, and counting on the original brakes.
1. switch to .658 5th
2. 51 lb tires inflated to 52
3. very rare use of AC
4. never exceed 60 mph (except on very long trips when time counts more than MPG)
5. always be alert to preserving momentum
RESULT...EVERY tank is over 60..(best tank 71) and this with a commute of 37 milesback and forth to McLean, VA on Interstate 66...(but ok, often before 5:30am and returning just at 3:00).
If anyone doubts my 60+ mpg number (usually 61 to 63), please call me and I will be happy to show you exactly how I have been able to do this.
pjt
Much of the guidance I have seen on increasing mpg is helpful, but leaves out something that has made a big difference in my mpg numbers-- accepted gap distance (space between you and the leading vehicle).
On interstates I try to leave 8 or so times my speed in feet (roughly). So at 60, I try for 480 feet or so. Then as soon as the lead vehicle brakes, shift to neutral and if necessary roll right up to the lead vehicle. Most of the time you will be able to accelerate again well before getting within 5 feet of the lead vehicle and you'll never touch the brakes.
If you have the extra time and patience for this kind of driving, the payoff can be exceptional. I also have taken the following steps to reduce fuel consumption in my '02 Golf TDI (with, btw, 157,000, and counting on the original brakes.
1. switch to .658 5th
2. 51 lb tires inflated to 52
3. very rare use of AC
4. never exceed 60 mph (except on very long trips when time counts more than MPG)
5. always be alert to preserving momentum
RESULT...EVERY tank is over 60..(best tank 71) and this with a commute of 37 milesback and forth to McLean, VA on Interstate 66...(but ok, often before 5:30am and returning just at 3:00).
If anyone doubts my 60+ mpg number (usually 61 to 63), please call me and I will be happy to show you exactly how I have been able to do this.
pjt
oysterengineer
Member
I certainly believe your mileage numbers based on my experience. Your Golf is likely ~600 pounds lighter then my Jetta. Not only due to the body style differences, but also due to the extra airbags that my car carries around.pjtremont said:
What is your experience regarding carbon build up in the intake from the EGR?
pjtremont
Member
experience with carbon buildup
I had a complete engine shutdown at 55kmiles due to carbon buildup. After cleaning the intake I reprogrammed to reduce this problem.
But after the switch to low sulfur fuel, I programmed back to stock. So far,no problems. BUT, I don't have enough miles yet to know if carbon will not again clog the intake.
I had a complete engine shutdown at 55kmiles due to carbon buildup. After cleaning the intake I reprogrammed to reduce this problem.
But after the switch to low sulfur fuel, I programmed back to stock. So far,no problems. BUT, I don't have enough miles yet to know if carbon will not again clog the intake.
meby
Veteran Member
NarfBLAST said:I'm thinking of installing a zerostart coolant heater for cold winters but maybe could use it in the summer too.
Considering a 1000watt unit it just depends how much electricity costs in your area. say 10 cents per kwh. lets splurge and run it for an hour...
At cold idle my Scangauge reads from .6 to 1.2 somewhere, lets call it 1.0L/hour. 1L of fuel costs 140 cents lately. so for 10 cents you get 1/14th of liter or you could run for 1/14th of an hour... multiply by 60 minutes thats 4.28 minutes.
So you could run the heater for half an hour to an hour or idle the car for two to four minutes for the same cost. But I would argue that using the elctric heater would get the engine much warmer than idling. Instead of idling that same ammount of fuel would get me aprox 15 to 30 seconds of driving at my average 5.0L/100km... that would not warm the engine that much either.
My conclusion is that it would definetly cost less to use the heater to bring the engine temperature up. But would the improvement in effecientcy be worth the trouble of plugging/unplugging you car? I think I would like to get used to plugging in my car daily for when they finally start selling plug in electric vehicles
How many L/hour do our cars use cold @ 55 mph? I usually start my car and go withing 30 seconds. I'm trying to get an idea how much I would save by taking off when the car is already warm, summer or winter.
NarfBLAST
Top Post Dawg
aprox 4 to 5 L/hour at 90km/hmeby said:
meby
Veteran Member
So in real life, it takes 4 miles it takes my car to warm up completely in the summer or about 5 in the winter. Am I only getting around 20 mpg when in the first mile and getting progressively better as it warms up? I realize the math is bit more complicated than that, anyone care to take a stab at what I would save to plug my car in for an 1/2 hour or and hour and see if it pays?
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meby
Veteran Member
Also, how much does the car use once its warm @ 55 mph on say level terrain.
I really need to buy vag com.
I really need to buy vag com.
NarfBLAST
Top Post Dawg
Or a ScangaugeII!! VAG-COM won't give you a running total of ammount of fuel you have used this trip! I have set up my Scanguage xGauges to read actual fuel used for the current trip and water temperature. (along with the usual instant fuel consumption and trip fuel consumption, can't live with out those) I will try and record this every morning and see how much fuel I use before the temperature reaches say 80 deg C (fully warm is 90degC). I will do this until my kit arrives for the heater and then by the time I actually get around to installing the heater I should have a good base line. Will be sure to post here. Anyone else tried this yet?meby said:Also, how much does the car use once its warm @ 55 mph on say level terrain.
I really need to buy vag com.
edit: I've done one trip and realized I need to make a spreadsheet... should I start a new thread when I get the spreadsheet going?
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meby
Veteran Member
Sure, new thread would be great. I don't think I have seen a thread addressing this specific idea. I'll be waiting gladly to see your results. I think i'll probably go for vag-com first so I can do stuff like mess with the egr cycle thingee among other things.
When I coast down hill in "drive" my scangague says 9999 miles per gallon. If I coast down hill in "neutral" then it varies around 200 - 400 miles per gallon. Is this true? Do I really get better mileage drifting in "drive" rather than "neutral?"
NarfBLAST
Top Post Dawg
True: coasting in gear zero fuel is consumed (wheels spin the engine)bockegg said:
Coasting in neutral requres fuel to spin the engine (fuel spins the engine)
rotarykid
Top Post Dawg
- Joined
- Apr 27, 2003
- TDI
- 1997 Passat TDI White,99.5 Blue Jetta TDI
DEpending on the situation you can use less fuel to travel farther in "N" than the staying in gear and coasting a shorter distance . So in situations where you can coast farther in "N" than staying gear you use less fuel in "N" . On grades where staying in gear doesn't shorten the coasting distance staying in gear is most efficient . Or if the distance needed to travel isn't long enough for staying in gear to hinder travel distance staying gear will be most efficient .bockegg said:
You have to judge each condition to figure whether staying out of gear or cruising in gear would be most efficient .
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NarfBLAST
Top Post Dawg
I think you meant whether staying in gear or coasting in neutral... I agree totally! I found huge benefits to my trip average by coasting down some realling long hills in neutral... Its amazing how far you can go when you take it out of gear! Scangauge will report some fuel being used, but if use a "current trip" xgauge you can just watch the average fuel economy climb! (average fuel consumption drop!)rotarykid said:
Tom Servo
Veteran Member
Did anyone ever find out about Wal-Mart (MurphyUSA)'s cetane numbers?
RI_TDI
Veteran Member
I don't know about Wal-Mart but I'm working on Valero (they have the best prices here in Austin). I just got back a pseudo-answer: "greater than 40". Duh. It came from the compliance department so the nature of the answer is understandable.
I wrote back and asked them to consult someone in refining / formulation for a more specific range, citing competitor's high levels and explaining that folks like us would pay a higher unit price because it actually gave us a lower cost of operation. I'll post the next response.
I wrote back and asked them to consult someone in refining / formulation for a more specific range, citing competitor's high levels and explaining that folks like us would pay a higher unit price because it actually gave us a lower cost of operation. I'll post the next response.
ozarkjeff
New member
MurphyUSA Cetane
I called and got a fellow at corporate that said for my terminal here in NW AR. the Cetane fluctuates but is very close to 45, the BTU's hang around 140,000 and they supply # 2 diesel all year round. ( no Winterizing the fuel in this area) I was impressed with his responses and though he hedged a bit on some answers, at least he had them. I also called Conoco hdqrs and BP as well. Neither of them had the numbers, even though the diesel in this area all comes from Razorback terminal. I'm sure it is just to standard # 2 ULSD specs. I'm staying with Murphys and adding Stanadyne to my 2006 beetle.Tom Servo said:
If I primarily drive my TDi 2 miles to work, and then let it sit for 4-5 hours, and then the same thing home, will that make my highway mileage go down? If so, will it take a while to get better mileage on road trips?
JettaJake
Veteran Member
Cruising or "road trip" mileage should show gradual improvement up through 60K miles or more. If work was but 2 miles away, I have doubts my TDI would be my daily driver, but regardless, sounds like you have a great excuse for more road trips!
mooniac
Member
A little story that happened yesterday. I was at a light and completely stopped . I just happened to look in the rear view mirror and saw a pickup truck approaching very fast, I kept looking and decided he was not going to stop in time. I quickly moved over to the next lane and this idiot slammed into the car that was in front of me. Anyway the police arrived and the woman who got hit tried to blame it on me for moving out of the pickup trucks way. I think the officer laughed inside as I laughed on the outside. I don't think I could have moved so fast if my engine was off. Something to think aboutSBAtdijetta said:It may give some extra wear on the starter sure, but safety? How is turning the motor off at long stop lights a safety issue? Please enlighten me on this...
Edit: In case you are thinking i turn the motor off while crusing or coasting no, I do not.
LumberJack5500
Veteran Member
Exactly why I don't bother shutting off the motor at lights, not to mention that by shutting off your motor it make take an extra few seconds than normal for you to start moving again as opposed to not shutting down. These couple seconds could be the difference between letting the cars behind you through the light or not, so essentially if you shut down and take long enough to get going again you could cause the cars behind you to get stuck in the light again and they will all be idling....which kind of negates the point of you shutting off your car in the first placemooniac said:
Do you think that I would be better off running my 4 cyl. gasser bug instead of the TDi for the short 2 mile trips to work and back?JettaJake said:Cruising or "road trip" mileage should show gradual improvement up through 60K miles or more. If work was but 2 miles away, I have doubts my TDI would be my daily driver, but regardless, sounds like you have a great excuse for more road trips!
One more question. I shut off while fueling, while some TDi drivers leave their cars running. Is there any advantage of leaving the car idle for short stops?
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NarfBLAST
Top Post Dawg
I think that taking gas bug for all your short trips would improve fuel economy in the TDI instantlybockegg said:
But seriously, I don't think that anyone is saying that taking longer trips in the tdi will clean it out or anything, just that the longer the trip the better the fuel economy for that trip. The TDI can get better mileage on shorts trips as well as long trips... Maybe if you lived somewhere really cold you might want to choose the gas because it might warm up faster.Please let me know who and where these TDI drivers who leave their cars running are so that I can tell them to STOP IT!!! There is no reason to leave your car running unless your battery is dead and you are on your way to get a new one or it is -40 outside and you have no other way to keep warm.
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This just happened in the statr of PA this summer. Two Jetta TDi'ers and one Chevy pick-up diesel.NarfBLAST said:I think that taking gas bug for all your short trips would improve fuel economy in the TDI instantly
Please let me know who and where these TDI drivers who leave their cars running are so that I can tell them to STOP IT!!! There is no reason to leave your car running unless your battery is dead and you are on your way to get a new one or it is -40 outside and you have no other way to keep warm.
Brock_from_WI
Veteran Member
Ya for short trips the mileage drops off. I have noticed about a 15% decrease in mileage for 3 mile trips, but the gasser was almost identical. Another difference was the TDI wasn't even off the cold mark and the gasser was up to temp. Then again 45 mpg vs 18 mpg