Newbies and Vets: Tips for better fuel economy!

rotarykid

Top Post Dawg
Joined
Apr 27, 2003
Location
Piedmont of N.C. & the plains of Colorado
TDI
1997 Passat TDI White,99.5 Blue Jetta TDI
That DSG is not going to help much either up here either, a manual would get better fuel economy up here with the varried terrain....

The best bet is going to be have somebody try to tweak the timing. Find someone who has has a vag com cam that can adjust the start of injection.
 

lagat

New member
Joined
Oct 13, 2017
Location
Miami
TDI
1.9 litre 4-cylinder 110hp (A4 type)
Gas mileage tips can help you reduce the amount of gas you use. If you are already following these tips, you are probably getting the best gas mileage your car can deliver.
Drive more efficiently
Keep your car in shape
Plan & combining trips
Choose a more efficient vehicle


__________________
Springfield Tow Truck
 

Arlene Zsilka

New member
Joined
Dec 30, 2017
Location
Michigan
TDI
2015 Sportwagen
A friend is a diesel engineer at a big 3 company. Did studies of fuel quality. He discovered BP Amoco was best, with fuel from Meijer stores being nearly equal, and about 10 cents per gallon cheaper. AVOID truck stops. Lowest quality, full of dirt to clog your fuel filter.
 

BleachedBora

Vendor , w/Business number
Joined
Oct 16, 2003
Location
Gresham, Oregon
TDI
'81 DMC-12, '12 Audi TT 418 hp/383 tq, '08 GL320 CDI 275 hp/448 wtq - '81 Caddy ALH, '04 Golf BEW 2" Lift, '85 HMMWV
Great link Lightflyer1! I've added it to the first page :).
Thanks!
-BB
 

tedd

Member
Joined
Oct 8, 2014
Location
uk
TDI
polo 1.4tdi-pd (AMF engine, 2001 SE spec)
Winter equipment trials update!!

-Task: eliminate mist from all internal windows.
-Equipment 2 x damp traps. cost less than £1 each from b&m etc.
https://www.bmstores.co.uk/products/dehumidifiers-4-x-250g-321193
example picture here:
https://www.ebay.co.uk/itm/Dehumidi...tch-Mildew-Remover-Caravan-Home-/222768226303

-insert 1 damp trap in driver and 1 damp trap in passenger pocket (fits nice and tight,larger side of trap to back, smaller side of trap to front)
-when switching car off overnight, set air direction knob to footwell + switch on air recirculate function then switch off car.

In the morning you will have no misted windows for a fast start.
(warming a diesel requires it to be driven, so you waste time/fuel idling for almost no heat).

Bonus feature-frost on outside clears slightly easier when no misting on inside of glass.
Tedd you are a genius!
 
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theodore

Active member
Joined
Aug 8, 2017
Location
Spokane, Wa.
TDI
2) 1996 b4 Passat
I have a 96 Passat, wvwhg83a3te072254 for a diesel it's "quick like a bunny". Has rocket chip stage three in the ECU, do not know nozzle size, but i did put a new turbocharger on it,not orginal engine but stock from a donor car, Owner before me had put WVO system(which destroyed engine)... Anyway we got these cars to get 45-55(like MK1&MK2 rabbits) but I suffer from Aledphootitis and unless im on the interstate using cruse control my miledge is low 30's.

I cant get the IQ within range, I think previous owner hammer mod or somthing. or mabye somthing to do w/chip? idk, thats why i here...

I building new engine right now and saving for a new(rebuilt) ip, trying to find a good head for the 1Z/AHU.

Seems to me exhaust and intake air is key, Go with the Flow..
I plan to get new exhaust from Downpipe(catecktome) 2.5" i suppose.(thk muffler maybe clogged omg.

Watch out for Ritzville cops!
Peace.
 

TDIPOWERMAN

Veteran Member
Joined
May 30, 2009
Location
Virginia
TDI
2000 Jetta TDI
Milage improvement experienced

I was recently amazed when I measured an obvious improvement with a cetane booster form BG product DFC PLUS pn 248. It boasts lubricity enhancement as well as injector cleaning abilities. I can verify the milage improvement of 10 to 15 % in my 2001 jetta as fact. Took a road trip from Va to SC and saw marked improvement. Normal 70 mph driving ussually nets 49-50 mpg, changed to 56-57 mpg. I have no sales interest in BG company products, just saying you may wishto try them, from your nearest dealer.:)
 

251

TDI Owner/Operator
Joined
May 11, 2002
Location
NW IN
TDI
2015 Passat TDI SEL
I was recently amazed when I measured an obvious improvement with a cetane booster form BG product DFC PLUS pn 248. It boasts lubricity enhancement as well as injector cleaning abilities. I can verify the milage improvement of 10 to 15 % in my 2001 jetta as fact. Took a road trip from Va to SC and saw marked improvement. Normal 70 mph driving ussually nets 49-50 mpg, changed to 56-57 mpg.
How many tanks have you used this product with? It may not be that good long term. In other words I doubt you will see an improvement of 5-6 mpg on every tank from here on out.

I always use an additive on each tank but did have a period where I didn't use it for about 3 months or so during one summer. My mpg's dropped slowly - wasn't obvious at first. A friend gave me a new additive to try and on the first tank I got 5 to 6 mpg better than before (almost identical to your experience with a different product) - mainly because the product cleaned my injectors out. If you use additive regularly then your injectors will remain clean so you won't keep getting an improvement in fuel economy after the "initial cleaning".

So run thru a few tanks and report back if you are still getting 5-6 mpg better after a few thousand miles. That is a better indication of if the chosen additive product is of real benefit or not.
 

Lightflyer1

Top Post Dawg
Joined
Sep 13, 2005
Location
Round Rock, Texas
TDI
2015 Beetle tdi dsg
Did you make the same exact trip under the same conditions without the additive? Comparing different trips under different conditions isn't really apples to apples. I would think that if it is as you say the industry would be going hog wild over those kinds of numbers.
 

251

TDI Owner/Operator
Joined
May 11, 2002
Location
NW IN
TDI
2015 Passat TDI SEL
Did you make the same exact trip under the same conditions without the additive? Comparing different trips under different conditions isn't really apples to apples. I would think that if it is as you say the industry would be going hog wild over those kinds of numbers.
Are you addressing me or TDIPOWERMAN with your questions? I'm assuming you meant TDIPOWERMAN as his claimed improvement in mpg numbers are twice what I observed when I ran additive for the first time that one summerafter not running same for a few months.
 

Apone

Member
Joined
Mar 19, 2017
Location
Owensboro
TDI
None
Also flow makes a difference i drive base in my egt gauge at 60 in 6th gear i flowing less air egt in the 730 ish out in 5th rpm goes up around 400 ish and egt down to 530 ish and mpgs go up , I drive 34 miles one way to work
 

Jetta_Pilot

Top Post Dawg
Joined
Apr 14, 2005
Location
West Hill, Ont. Mexico mid October 2019 to end of
TDI
2015 Passat Highline TDI Candy White (SEL Premium) gone 2002 Jetta TDI
Mpg figures:

Any numbers are always circumspect since conditions vary from day to day.
Wind, Temperature, Humidity, Traffic etc.
Unless you can duplicate the same exactly, it's not really true.



Why do you think those government Mpg numbers are different.
They test the car in an enclosed area with only the powered wheels on a roller (Dynometer), same humidity, same temperature, no wind and of course no traffic.
 

hajes

Active member
Joined
Jan 16, 2017
Location
Earth
TDI
Skoda "Hilda" Octavia HR I
always keep revs below 1800rpm...it will save lots of fuel, destroy clutch, crankshaft bearings and more ;-)

best power/economy is where turbo is in its most effective area...which means for every factory tuned TDi at around 2500-2700rpm or mid way between max torque/power...in my car 1850-4000rpm.

At 2500rpm I get 700km per 55l tank...3000rpm 600km per tank...grandpa style at 2000rpm...who knows, maybe 1000km per tank...my record when I drove really slow that I felt i could walk faster...I have got 800km per tank.

Car is a transportation device for reaching quickly point A>B...if I want to save, I will go by bus/train
 

Jettax3

New member
Joined
Oct 4, 2018
Location
Southern OH and Halsey OR
TDI
1998 Jetta, 2000 Jetta (x2)
Hi, new member here. New to forums as well, hope I'm doing this right. In reading all these pages, I saw very little reference to a plugged cat. In my case this made a 10mpg difference when I removed it. That would be highway miles btw. Also it's possible I slowed down a bit on average the last time I drove to OR, so that would have a bearing on the mileage as well. Anyway, I got 47-49.6 mpg in late June, a/c running wide open all the time (sorry I like to be comfortable when I drive my car;) I drive I-80, last year similar conditions yielded just under 40 mpg. Like I said, I think I slowed down on average (sorry not documented) but I was pretty happy with the mpg I got. So a question: if I tune my car (injectors, stage 2 cam, etc) will I see an improvement on those long road trips? I understand that in the truck world, if you tune your truck, and keep your driving habits the same, your mileage is guaranteed to increase. Obviously with all that torque on tap, it would be hard, at least at first, to drive exactly how I did before. So question is mostly aimed at the road trip mpg.
Great site. Lots of info that I didn't know before!
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
If you’re looking for MPG improvements, first and foremost make sure everything is working as it should from the factory. You’ve found a plugged cat, make sure everything else is working too. Air filter, timing (pump and cam), vnt actuator, egr/intake is clean, etc.

I’d recommend a tune only and a switch to low viscosity engine and transmission oils to improve MPG. Maybe taller tires (205/70/15) the next time they need to be replaced (make sure you account for the extra distance traveled). A stage 2 cam won’t make much difference if any so they’re not high on my list. Injectors are ok if you need them, but they also typically require a new clutch if not detuned and that can get a bit expensive and time consuming. If you’re dmf is making noise or you’ve already replaced the clutch then nozzles for sure, but the tune and oils are the most important thing
 

emdog

Member
Joined
Sep 27, 2018
Location
WV
TDI
Stock, '13 2.0 Bug, 45kmi, DSG
Not an actual nube, and, Day-amn! Well that sux! I just wrote a dissertation about my 2mo old new/used '13, Candy, 45K, cpo, dsg, so far 35.1mpg hgwy/city(10-25 over the limit) Bug girlfriend, and as I tried to copy it, 'just in case', something went kazookie & I lost it to the ether
And a somewhat funny, very long rant about a great dlrship mgr, & a wet behind the ears, mom still dresses him, svc tkt cluck who's way younger than my 55yrs (I'm 68) as 1 sun more than a shade tree mechanic. Oh well... I'll be back bec I want the skinny on Malone et al tuning etc
So, off to the dlrship to rub some real knowledge into the cluck's nose, & maybe his eye if he cops another attitude about my reality diagnostic 'tool'/stuck on my mud-slicked surfaced, 30* drvway, vs his/tech's, 'both front wheels turn when it's on the lift/fwd is ok' diagnosis.
 
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eagle

Veteran Member
Joined
Apr 14, 2004
Location
North Carolina
TDI
2013 Jetta
1. The sooner you get to a higher gear the better (lower RPM = less waste)

2. The power curve for the TDI shows the best efficiency at 100% load, between about 1500 and 2500 RPM.

So...the most efficient way to get to speed should be flooring it, skipping gears (as long as you stay in the efficient RPM range).

Since adopting this method my mileage improved at least 15%.

This stands in direct contradiction to the "Take it easy accelerating" rule. Anything wrong with my logic, or my observations?
I know I'm quoting an 11-year-old comment, but I seem to recall that I read that flooring it and shifting quickly was the best way to go too.

I've been looking for the old FAQ from the ~2006 timeframe but haven't found it yet.

My understanding is that TDIs generate their economy at speed, so the best thing to do is to not waste time accelerating, and to accelerate as quickly as possible -- and then to stay at speed and not slow down.

Am I remembering this correctly?

I recently got a new-to-me 2013 Jetta TDI, and I'm wanting to run it efficiently. I'm not a hypermiler, but I would like to get 35+ in the city, and 45+ on the highway, and I'm sure it's possible even with my driving conditions.

Thanks.
 

Lightflyer1

Top Post Dawg
Joined
Sep 13, 2005
Location
Round Rock, Texas
TDI
2015 Beetle tdi dsg
Depends on your driving conditions. Mostly highway and I would agree with what you posted, in the city not so much. Accelerating hard over and over again in town should kill your economy. If you only have to do it a few times per tank, probably the way to go. I have no trouble getting 35 mpg (urban driving) in my Beetle just driving normally. It should be easier for you in the Jetta.
 

eagle

Veteran Member
Joined
Apr 14, 2004
Location
North Carolina
TDI
2013 Jetta
Thanks. I’ll see what I can do. Unfortunately (fortunately?) my commute is only 5 miles, so it takes forever to get through a tank.
 

Lightflyer1

Top Post Dawg
Joined
Sep 13, 2005
Location
Round Rock, Texas
TDI
2015 Beetle tdi dsg
With only a 5 mile commute don't ever expect to get stellar fuel economy. The engine can't even get warmed up in that amount of time. A TDI isn't the best at all for that kind of driving. You have to be careful to let regens complete when your commute is that short. This is where a hybrid or fully electric car shines.
 
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