Newbies and Vets: Tips for better fuel economy!

BleachedBora

Vendor , w/Business number
Joined
Oct 16, 2003
Location
Gresham, Oregon
TDI
'81 DMC-12, '15 GL350 CDI 275 hp/448 tq - '81 Caddy CJAA, '05 E320 CDI 250hp/450 tq, '23 ID4 AWD Pro S Plus
Still, I'd consider that pretty sub par--I assume you are NOT using the computer for mileage tracking?

Plan a road trip, fill completely, drive it at least 200 miles, preferrably more than that. Set the cruise on 60 and don't touch it. Let us know what you get. :)

if all you do is city driving, while "taking advantage of the torque" while having tons of stop and go, then I can see 26 as possible. As much as it galls me to say so, those are the conditions where a hybrid would have served you better. (*Peers around for a Diesel-electric hybrid :rolleyes:*)

Good luck!
-BB
 

johnchitown

Member
Joined
Apr 18, 2008
Location
Chicago
TDI
06 Beetle TDI
Thanks to all who replied.

BleachedBora said:
Still, I'd consider that pretty sub par--I assume you are NOT using the computer for mileage tracking?
Plan a road trip, fill completely, drive it at least 200 miles, preferrably more than that. Set the cruise on 60 and don't touch it. Let us know what you get. :)
if all you do is city driving, while "taking advantage of the torque" while having tons of stop and go, then I can see 26 as possible. As much as it galls me to say so, those are the conditions where a hybrid would have served you better. (*Peers around for a Diesel-electric hybrid :rolleyes:*)
Good luck!
-BB

Yesterday, I hooked up a Scan Gauge II and took my Beetle out for some highway driving to see the difference. I drove only about 120 miles. 85% percent of if expressway going at steady clip that went from 55 to 70 MPH. the balance was suburban driving goinng 30 to 45 with few stops.
To my total amazement, when I pulled into my garage, the SG showed just 28 MPG for the trip.
My beetle has 17" inch factory wheels - does that fact need to be programmed into the SG or is part of the engine info?
Hope to hear back.
Thanks again.
John
 

johnchitown

Member
Joined
Apr 18, 2008
Location
Chicago
TDI
06 Beetle TDI
BleachedBora said:
Still, I'd consider that pretty sub par--I assume you are NOT using the computer for mileage tracking?

Plan a road trip, fill completely, drive it at least 200 miles, preferrably more than that. Set the cruise on 60 and don't touch it. Let us know what you get. :)

if all you do is city driving, while "taking advantage of the torque" while having tons of stop and go, then I can see 26 as possible. As much as it galls me to say so, those are the conditions where a hybrid would have served you better. (*Peers around for a Diesel-electric hybrid :rolleyes:*)

Good luck!
-BB
I use the torque in the city but I don't mash the pedal down. At least it is still double what my Subaru Tribeca was getting:)

My problem with Hybrids is what are we doing to the environment making those toxic batteries and what happens when they go into the land fills.
 

40X40

Experienced
Joined
Feb 12, 2006
Location
Kansas City area, MO
TDI
2013 Passat SEL Premium
johnchitown said:

Yesterday, I hooked up a Scan Gauge II and took my Beetle out for some highway driving to see the difference. I drove only about 120 miles. 85% percent of if expressway going at steady clip that went from 55 to 70 MPH. the balance was suburban driving goinng 30 to 45 with few stops.
To my total amazement, when I pulled into my garage, the SG showed just 28 MPG for the trip.
My beetle has 17" inch factory wheels - does that fact need to be programmed into the SG or is part of the engine info?
Hope to hear back.
Thanks again.
John

You have to calibrate the SGII to whichever car it is used with. This takes several tanks or fillups.
Read the manual follow the directions for initial setup. Then each time you top off the tank (completely full, not just to the click) tell the SGII how much fuel you put in.


johnchitown said:
My problem with Hybrids is what are we doing to the environment making those toxic batteries and what happens when they go into the land fills.
Car batteries are recycled now, not put into landfills. Yes, some still end up there but they are the exception, not the rule. On the other hand, what we as a society do with small batteries like AA ni-cads is irresponsible.

Bill
 

johnchitown

Member
Joined
Apr 18, 2008
Location
Chicago
TDI
06 Beetle TDI
40X40 said:
You have to calibrate the SGII to whichever car it is used with. This takes several tanks or fillups.
Read the manual follow the directions for initial setup. Then each time you top off the tank (completely full, not just to the click) tell the SGII how much fuel you put in.
Car batteries are recycled now, not put into landfills. Yes, some still end up there but they are the exception, not the rule. On the other hand, what we as a society do with small batteries like AA ni-cads is irresponsible.
Bill

Thanks, I will check set up and follow up.

I agree about the battery comment.
 

Kosh

Member
Joined
Dec 16, 2007
Location
Ann Arbor, MI/ Hatfield, MA
TDI
2006 Jetta A5
Keeping your speed down is the best way to increase fuel economy. 60MPH is when the areodynamic drag starts to really cause you to use more fuel, I try to never go faster than 58 on the highway. I also slow down when going up hills losing the speed I gained by going down the previous hill. This is the method I use to get 60MPG on all my highway tanks.
 

TheDPR

Well-known member
Joined
Jun 4, 2007
Location
SW Virginia
TDI
2001 Beetle
Does it *really* matter which station you get your fuel at? Especially in less urban areas, aren't all the gas stations supplied from a common reserve?
 

dieselsipper

Veteran Member
Joined
Apr 29, 2008
Location
ON
In the original post, one of the rules stated to put your tire pressure to 90% of max value rated on the sidewall of your tires. On my 04 Jetta, the sticker inside the rear passenger door shows a recommended 8-9psi difference in pressure from front to back, back being the higher pressure. I suspect that this has something to do with the handling characteristics of the vehicle. So my question is, do you make the high psi to 90% and then still maintain the 8-9psi difference from back to front? I have been doing this for a few weeks now and my mileage has improved, but should I just go to 90% all the way around? Opinions please!!!
 

NarfBLAST

Top Post Dawg
Joined
Mar 3, 2002
Location
Waterdown, Ontario, Canada
TDI
2001 Golf 5MT
dieselsipper said:
In the original post, one of the rules stated to put your tire pressure to 90% of max value rated on the sidewall of your tires. On my 04 Jetta, the sticker inside the rear passenger door shows a recommended 8-9psi difference in pressure from front to back, back being the higher pressure. I suspect that this has something to do with the handling characteristics of the vehicle. So my question is, do you make the high psi to 90% and then still maintain the 8-9psi difference from back to front? I have been doing this for a few weeks now and my mileage has improved, but should I just go to 90% all the way around? Opinions please!!!
VW has the most confusing PSI ratings. Mine has a range for the front, and a different range for the back depending on whether you have half load or max load. Its retarted. I keep mine at 38psi all around, but mine are 205/75R15's which are 8.5% taller (longer) than stock so I'm on my own. With vw's "range" you are kindof on your own to begin with tho because if the CRAZY RANGES the list for their tires.

Not like my wife's Mazda... it just says "32"... well thats easy I just leave em at 32 because they are 45 series tires (low profile) and I suspect they are more sensitive to changes in presure.

Tire pressure is a personal thing... kind like your "sleep number mattress". Try to go as firm as you can tolerate the ride and without exceeding 90% of the maximum on the sidewall and without wearing a bald patch down the center of the tire.
 

ruking

Top Post Dawg
Joined
Mar 27, 2003
Location
San Jose area, CA
TDI
2003 VW Jetta, 5 M, Reflex Silver: 09 Jetta, 6 Sp DSG, Candy White: 12 VW Touareg, 8 Sp A/T, Flint Gray
dieselsipper said:
In the original post, one of the rules stated to put your tire pressure to 90% of max value rated on the sidewall of your tires. On my 04 Jetta, the sticker inside the rear passenger door shows a recommended 8-9psi difference in pressure from front to back, back being the higher pressure. I suspect that this has something to do with the handling characteristics of the vehicle. So my question is, do you make the high psi to 90% and then still maintain the 8-9psi difference from back to front? I have been doing this for a few weeks now and my mileage has improved, but should I just go to 90% all the way around? Opinions please!!!

To answer your question first, NO! Your rears are over inflated. If I understand what you have done, you have 40 psi fronts and 48/49 psi rears. Come down to 90% all around 40 psi (40/44 max sidewall pressure=90%) as a base line, then adjust as necessary.

Actually the operative thing happening is LOAD carrying capacity in keeping with handling characteristics. So IF you happen to run your vehicle more than not, at or close to the LOAD capacity, then yes, I'd use the 41 psi (03 Jetta) or whatever YOUR tire sticker says (03 Jetta baseline: half load-26 psi F/R: full load-30 psi front 41 psi rear. )

I run 38-36 psi, fronts, 38-34 psi, rears with -2 in the rears most of the time. The difference of -2 #'s in the rears are to maintain the understeer characteristics. The reason for the 2# range is so I can ignore TP measurements for UP to 2 months (loss of -1# per mo). Much past 38 psi is too hard for my SOTP's. If you want further explanations let me know.

I have already stated my fuel economy. I probably should also say that the oem tires GY LSH's I have done the above paragraph on are going on 107,000 miles and will probably be good to at least the next rotation @ 110,000 miles.
 
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NarfBLAST

Top Post Dawg
Joined
Mar 3, 2002
Location
Waterdown, Ontario, Canada
TDI
2001 Golf 5MT
ruking said:
The difference of -2 #'s in the rears are to maintain the understeer characteristics.
I thought it had everything to do with load rating.

Example in my golf: at half load VW recommends less air in the rear than in the front (because the engine end is heavier than the cargo end)

At max load VW recommends more air in the rear than in the front (because the cargo end is heavier than the engine end)

I heard from someone that in europe some gas stations have a chart that tells you what psi to inflate your tires to based on the number of passengers in your vehicle.
 

ruking

Top Post Dawg
Joined
Mar 27, 2003
Location
San Jose area, CA
TDI
2003 VW Jetta, 5 M, Reflex Silver: 09 Jetta, 6 Sp DSG, Candy White: 12 VW Touareg, 8 Sp A/T, Flint Gray
Yes I said that, you just quoted the part that I added for understeer characteristics. :) But no, not all to do with load characteristics. So for example if that were true, since most of the weight is carried by the front (static 2 to 1, dynamic, i.e., in some stopping behaviors 80-90/20-10) , most to all of the time, it only makes sense for example that the fronts have 41 psi for obvious reasons, they do not.
 
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izak

Member
Joined
May 24, 2008
Location
Northern Illinois, USA
TDI
2006 Jetta TDI
rotarykid said:
Coasting in "N" while at lower speeds in city driving will allow you to go farther without throttle input saving fuel . Also killing the engine when coasting while the engine is still cold can save fuel using your momentum to restart the engine when acceleration is required . Killing the engine should be avoided once the engine is warmed up due to the extra heat in the turbo.
I had heard once that coasting was illegal. Don't know for sure.
 

ruking

Top Post Dawg
Joined
Mar 27, 2003
Location
San Jose area, CA
TDI
2003 VW Jetta, 5 M, Reflex Silver: 09 Jetta, 6 Sp DSG, Candy White: 12 VW Touareg, 8 Sp A/T, Flint Gray
izak said:
I had heard once that coasting was illegal. Don't know for sure.
Check your DMV regulations, but in CA it IS illegal. However like many traffic laws (keep right except to pass) or lack of using signals, it is RARELY enforced. It is dangerous, which is why it is outlawed, but this is usually discovered only long after the catastrophic event and folks are either dead or injured or both.

The other oxymoron is that TDI engines really function best under load and NOT idling. Any TDI guru will tell you idle as little as possible. Coasting increases idle time!? Idling is normally associated in static. However idling when in motion is still not good.
 
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ruking

Top Post Dawg
Joined
Mar 27, 2003
Location
San Jose area, CA
TDI
2003 VW Jetta, 5 M, Reflex Silver: 09 Jetta, 6 Sp DSG, Candy White: 12 VW Touareg, 8 Sp A/T, Flint Gray
rotarykid said:
If you drive a stick you are in "N" as much 30 % or more of the time while driving in city traffic . The laws you speak of are to prevent some idiot from trying to coast down a mountain .
Indeed I do at times (doesn't everybody?) drive a stick in city traffic. Are you saying then that idling is good? I said what I said and the situation you mentioned really doesn't change things. For me, if it looks like I will be idling more than 45 sec, I look to shutting down the engine. A clearer example would be at a R/R X ing, which I ALWAY's seem to time perfectly when the LONGEST train needs to go by! UPSHOT SHUT DOWN!
 

BleachedBora

Vendor , w/Business number
Joined
Oct 16, 2003
Location
Gresham, Oregon
TDI
'81 DMC-12, '15 GL350 CDI 275 hp/448 tq - '81 Caddy CJAA, '05 E320 CDI 250hp/450 tq, '23 ID4 AWD Pro S Plus
I ran my Michelin Hydroedges at 35 (rated at 44) and they wore out the edges way before the center--rotated every 5,000 miles, they lasted 30,000 miles out of a 90,000 mile warranty. That was also back when my mileage was in the high 30s to low 40s. I have a set of Michelin Pilot Exalto AS tires now, running at 40 (rated 44) all around, and after 30,000 miles (rated for 40ish) they are wearing perfectly on all corners. Haven't even rotated them yet--they are all identical wear.

I think I could have got another 30,000 miles or so out of the Hydroedge had I had more pressure in them. Centers still had a ton of tread but the sides were completely shot.

Anyway, YMMV, so find something that works for you, but generally speaking with VWs you want to run on the higher side of pressure anyway.
-BB
 

NarfBLAST

Top Post Dawg
Joined
Mar 3, 2002
Location
Waterdown, Ontario, Canada
TDI
2001 Golf 5MT
I think what Rotarykid is trying to say is that sometimes you get better fuel economy coasting out of gear than coasting in gear becasue the TDI uses very little fuel at idle and leaving it in gear would cause you to slow down too much relative to coasting out of gear and the cost to your speed outweighs the ammount of fuel saved by not idling. ie it would take more fuel to maintain/accelerate then it would to just coast/idle.

A Scangauge helps sort this out, and I've seen that coasting out of gear uses very little fuel and can sometimes make more sense than putting it in gear to get that perfect "zero fueling"... but I actually prefer to use cruise control in as high a gear as possible and let the beautiful German Engineered Kruise Komputer figure out the fueling in my car.
 
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Hot Georgia

Veteran Member
I've ran all my vehciles (about 12) with 100% max sidewall cold pressure. The set on my current vehicle went 88,000 miles and wore evenly across. I often corner pretty hard to keep momentum and haven't noticed any difference in traction with the suggested 32vs51. (51 is the Max cold rating)

I have a very harsh ride but enjoy an additional ~5MPG.

-Steve
 

ruking

Top Post Dawg
Joined
Mar 27, 2003
Location
San Jose area, CA
TDI
2003 VW Jetta, 5 M, Reflex Silver: 09 Jetta, 6 Sp DSG, Candy White: 12 VW Touareg, 8 Sp A/T, Flint Gray
Hot Georgia said:
I've ran all my vehciles (about 12) with 100% max sidewall cold pressure. The set on my current vehicle went 88,000 miles and wore evenly across. I often corner pretty hard to keep momentum and haven't noticed any difference in traction with the suggested 32vs51. (51 is the Max cold rating)

I have a very harsh ride but enjoy an additional ~5MPG.

-Steve
My swag using your experiences and mine (107,000 miles running 38/44 psi or 85/86 % would suggest that 86% of 51 (44 psi) psi would soften up your ride and still keep your chances high of getting 88k or maintaining your longer wearing setting.
 

verylongdrive

Veteran Member
Joined
Feb 10, 2005
Location
HSV
TDI
Golf,2001
MAF performance (and debug):

Is there a reading that one can see in VAGcom that would show whether the MAF is reading correctly at idle?

My '01 starts and stops limping somewhat randomly (and it goes away with the MAF unplugged), and I'd love to be able to wiggle the connector and the wires while so I can see where it's actually losing contact.

Additionally, back on the topic of this thread, while the MAF is basically working, I'd like to check if it is performing fully the way it should.

thanks.
 
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BleachedBora

Vendor , w/Business number
Joined
Oct 16, 2003
Location
Gresham, Oregon
TDI
'81 DMC-12, '15 GL350 CDI 275 hp/448 tq - '81 Caddy CJAA, '05 E320 CDI 250hp/450 tq, '23 ID4 AWD Pro S Plus
You want to go to the part that shows MAF specified and MAF actual, with the actual you want under full throttle to see a reading above 850 (or is it 950?) Point is if you have something in the 400-600 range your MAF is toast.
-BB
 

nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
SOLD 2010 Touareg Tdi w/factory Tow PCKG
Sweet!

I think this is helpful to those trying to preserve mpg or in tracking down MAF failure symptoms, a leading cause of bad mpg.

I'm going to code that in tonight.
 

zachmain02

Member
Joined
Jan 10, 2008
Location
CA
TDI
06 Jetta
"If you are running a cone filter (like K&N) you don't even have to check it, it's probably bad already. A stock air filter flows better than a K&N and it won't kill your sensor." - BleachedBora


i have read that the K&N filters flow better, not worse. dont care to argue the point, i just have a K&N and am wondering if i should take it out to save the MAF. anyone have a good pros/cons of K&N vs. stock?
 
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