Need Ideas, 01 ALH Still Getting Poor Mileage

DustyB

Veteran Member
Joined
May 6, 2007
Location
Springfield, Oregon
TDI
2001 Jetta
My 2001 Manual ALH is refusing to get decent fuel economy. Intake is as clean as a whistle, EGR is as clean as it can be. I'm running B5 instead of using Power Service. I haven't got the exact data from fueling up yet but Scanguage is saying about 36, after seeing the position of the gauge at 175 miles on the tank (one mark from half) its doing the same as it was before cleaning the intake.

Even though I don't have precise data the gauge is at the same position its been at this mileage since I bought this car, so roughly no change. I'm wondering if the car sitting at 10 to 15 load at warm idle has something to do with it? It also sits at about 75% load at 60 MPH on straight and flat highway. Other than that can I get ideas for things to start checking / replacing?
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
How's your driving habbits? Do you lean toward driving it like you stole it....revvving each gear to 4 grand and above before shifting? Is the majority of your driving city-urban? Are you one those drivers that cruise around on the streets in 4th gear seldom shifting into 5th gear? Do you have a "road trip" base line MPG fill-up that reveals its potential on the road?

Lastly, are you basing your "milage" on ScanGauge real-time readings or from fill-up to fill-up. Are you venting the tank at each fill-up?

Data from hard facts is the best way to determine overall MPGs.

The lowest milage fill-up I have ever done with my 2000 TDI was just under 44 MPG. The overall average is just under 51 MPG with a total of 330 fill-ups (221,248 miles that I have driven it, purchased used with almost 45k on it).
 

Black00Jetta

Veteran Member
Joined
Oct 15, 2003
Location
Relocated to AZ
TDI
2000 Jetta GLS Black 5spd
Have you checked for a dragging brake problem? I would think if this was a problem, you would have smelled it by now.
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Idling only consumes about .30 litre of fuel per hour .......... unless it is a *ell of lot of idling, that's not going to account for his fuel economy being in the mid-to-high 30s.

I've done the Highway 127 Yard sale (miles and miles in August each year) and let my TDI idle with AC on, stop after stop..... fuel milage has always been about 44 to 45 mpg during this annual event!

The City/Urban driving is a killer on TDI milage ....... eats up fuel getting the mass moving!

As I stated previously, I question his means of tracking fuel consumption! In reality, it may not be as bad as he's thinking!
 

DustyB

Veteran Member
Joined
May 6, 2007
Location
Springfield, Oregon
TDI
2001 Jetta
Couple of things:

I shift at about 2800 RPM when it's cool, and about 3200 when it's warm. I've also been told I drive too slow. Venting isn't really an option in Oregon because one it's been made illegal and two I'm not allowed to pump my own gas. (Go figure)

I get real time stats from the Scanguage but most of my data comes from filling the tank to the top then dividing the miles by the gallons placed in the tank, venting the tank would only lower my expected MPG. I have never filled my tank beyond 13 gallons. Also it's pretty obvious that when the Fuel Light comes on and I have 450 miles on the tank, I fill it and I put about 12.9 gallons in, I'm not getting 50 miles to the gallon.

Also about 80% of my mileage is on the highway.

I'm going up to Vancouver this weekend to pick up leather seats so I've contacted Old Poopie, I don't know if he works on the weekends though, I'm hoping he can check my timing.
 
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thebigarniedog

Master of the Obvious
Joined
Oct 14, 2007
Location
Fail Command (Central Ohio)
TDI
1998 Jetta tdi
DustyB said:
Couple of things:

I shift at about 2800 RPM when it's cool, and about 3200 when it's warm. I've also been told I drive too slow. Venting isn't really an option in Oregon because one it's been made illegal and two I'm not allowed to pump my own gas. (Go figure)

I get real time stats from the Scanguage but most of my data comes from filling the tank to the top then dividing the miles by the gallons placed in the tank, venting the tank would only lower my expected MPG. I have never filled my tank beyond 13 gallons. Also it's pretty obvious that when the Fuel Light comes on and I have 450 miles on the tank, I fill it and I put about 12.9 gallons in, I'm not getting 50 miles to the gallon.

Also about 80% of my mileage is on the highway.

I'm going up to Vancouver this weekend to pick up leather seats so I've contacted Old Poopie, I don't know if he works on the weekends though, I'm hoping he can check my timing.
Couple of suggestions from the peanut gallery:

1) Coast in gear followed by neutral coasting (downshifting waste momentum which waste fuel);
2) Get upgraded balanced injectors from Frank;
3) Use the scangauge to train your right foot.
 

DustyB

Veteran Member
Joined
May 6, 2007
Location
Springfield, Oregon
TDI
2001 Jetta
thebigarniedog said:
Couple of suggestions from the peanut gallery:

1) Coast in gear followed by neutral coasting (downshifting waste momentum which waste fuel);
2) Get upgraded balanced injectors from Frank;
3) Use the scangauge to train your right foot.
I coast in gear like a fool, and I keep the throttle position at about 20 to 25 percent (at highway speed) is that where it should be?

Fuel system is where I'm looking next, but who is Frank?
 

far_cry

Veteran Member
Joined
Dec 29, 2009
Location
Israel
TDI
octavia 1.9 TDI alh
my octavia tdi with 300000km auto trans
it gets one liter for 10km, yes its very poor,but
i drive the car to work one way 18 km ,a lot of traffic light aggressive start from stop, high speeds at short time,so i think its very good. if i have gasoline engine ,i think i will be broke

and here in israel no way that tdi diesel will get 18 km for 1 liter
i think that the fuel quality is ****,how can i know that
 

friech

Well-known member
Joined
Sep 4, 2008
Location
Wasilla, Alaska
TDI
2002 Jetta Manual (formerly and Auto) transmission
DustyB said:
Couple of things:

I shift at about 2800 RPM when it's cool, and about 3200 when it's warm. I've also been told I drive too slow. Venting isn't really an option in Oregon because one it's been made illegal and two I'm not allowed to pump my own gas. (Go figure)
Having lived in Oregon for several years (before I moved out of there), how are they going to know you did a ventoctomy. Are you going to tell the fuel station manager? Unless the guy/gal pumping the fuel is a TDI club member, they wont know. How does Oregon enforce this if someone bought a vented TDI from another state that doesn't outlaw this crime!;)

Also, if your a Pacific Pride fueling station member, you can pump your own fuel there. It's a commercial fueling place but individuals can apply for an account with them. There are about 4 stations in the Springfield/Eugene area.
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Well, without reservation, I'll say you're not going to know much about your fuel consumption using a ScanGauge (I have one... it is always off and I VENT to the top every fill-up). I VENT with the little valve ..... it works just fine and that's its purpose. Oh, the ScanGauge is fun and gives some other pretty interesting data... but, it is not a true indicator of fuel consumption. (I know the hard-core users are going to jump all over these ScanGauge comments.) Actually, on several road trips in my '95 Blazer, I've got better real world data comparison out of the ScanGauge than ever with the TDI.

The 330 fill-ups entered in my rather elaborate multi-page Excel spreadsheet reveals the true fuel consumption ...... tank after tank, I fill it until it's almost running out, VENTED of course! Otherwise, I would be less than guessing what the engine is doing.

How many fill-ups have you done? How long have you owned the car? The questions are to determine if you have a running history that provides enough info to make a judgement about the overall fuel comsumption of the engine!
 

DustyB

Veteran Member
Joined
May 6, 2007
Location
Springfield, Oregon
TDI
2001 Jetta
Friench, I've never been interested in a ventectomy I'm looking for shorter tanks right now so I can get more results quicker after changing something with the car. The maximum I put in is 13 gallons.

Also I filled up today and I got 36 MPG the Scangauge was .8% off.

I have owned this car for seven months in that time I've done probably twenty or so fill ups maybe less, I have yet to break 40mpg.

I've tried every type of drive style there is slow, fast, shift high, shift low. The fact is that there is something wrong with the car.
 
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dieselfuel

Veteran Member
Joined
Dec 28, 2008
Location
ohio
TDI
2003 Jetta TDI
DustyB,

O.k., your mileage is less than par. Would you say the car runs sluggish?

Could be injectors and/or nozzles.

I'm have the same problems with my '03. I'm starting to think I need new injectors and/or nozzles. I'm down to 33 mpg w/5 speed man. trans.

df
 

jetta 97

Vendor
Joined
Dec 25, 2008
Location
Dallas (McKinney) ,TX ,USA
TDI
2 X Jatta MK5 2006
First no idling on TDI . Start your car wait 30 sec. put seat belt and drive. The oil in TDi is designed to work in cold and hot days same way.Of course you have to use VW 505.00 or VW 505.01 oil.
For example:
if you idling your car every day about 30 min. and let say you drive car 2 weeks with 1 tank. That is about 0.6 gallons waste of fuel .
So if you go 450 miles with 12.5 gallons = 36 MPG
But if you minus 0.6 gallons from 12.5 it will be 450 :11.9= 37.82MPG .
This number is very good in this part of year in Oregon. MPG it can drop up to 5MPG in winter time then summer time.
50 mpg you can get on very sunny day ,with out wind and cold and that is 100% hwy millage. Not in middle of winter.

My car will get 42 in summer time ,but in winter time it will go from 37-39. And I live in TX witch is winter time is like Spring time in Oregon.
 
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jetta 97

Vendor
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Dec 25, 2008
Location
Dallas (McKinney) ,TX ,USA
TDI
2 X Jatta MK5 2006
dieselfuel said:
DustyB,

O.k., your mileage is less than par. Would you say the car runs sluggish?

Could be injectors and/or nozzles.

I'm have the same problems with my '03. I'm starting to think I need new injectors and/or nozzles. I'm down to 33 mpg w/5 speed man. trans.

df
Same as I said in post #16. It is winter time and this winter is very cold and getting very long. Winter fuel is to much different then summer fuel and plus car run much longer to get hot then is summer time.
As we know fuel temperature and engine temperature regulate MPG also.
 

DustyB

Veteran Member
Joined
May 6, 2007
Location
Springfield, Oregon
TDI
2001 Jetta
I don't idle my car at all, I was saying at a stop light (idle) my car is at 10% load.

Since cleaning the intake the car runs awesome, I got at least 50% more power out of the car after cleaning the intake and EGR. I would tend to agree that it's winter fuel but it's been getting the same exact mileage (36 MPG) on the dot ever fuel up since the day I bought it.

I'm going to be paying a visit to Old Poopie this Monday, I'm hoping he can set the car straight.
 

Nevada_TDI

Top Post Dawg
Joined
Aug 17, 2008
Location
Reno, sort of...
TDI
2001 Jetta TDI
Dusty,
My 01 had 135K on it and my fuel economy was never spectacular. After I replaced the head (due to a broken timing belt) I got Franko6 to upgrade my injectors to the Sprint 520's and now I consistently get 600-630 plus miles before the low fuel light comes on. My tank is vented so that is worth another 80-90 miles per tank. The Sprint nozzles are great, more power than before and better consistent mileage too.
Frank is Franko6 and one of the trusted vendors and repair shops on this site.
 

DustyB

Veteran Member
Joined
May 6, 2007
Location
Springfield, Oregon
TDI
2001 Jetta
Nevada_TDI said:
Dusty,
My 01 had 135K on it and my fuel economy was never spectacular. After I replaced the head (due to a broken timing belt) I got Franko6 to upgrade my injectors to the Sprint 520's and now I consistently get 600-630 plus miles before the low fuel light comes on. My tank is vented so that is worth another 80-90 miles per tank. The Sprint nozzles are great, more power than before and better consistent mileage too.
Frank is Franko6 and one of the trusted vendors and repair shops on this site.
This is the information I'm looking for, Pop testing and whatnot are worth the extra $150? Did you have poor performance whilst your injectors where not working right?
 

dieselfuel

Veteran Member
Joined
Dec 28, 2008
Location
ohio
TDI
2003 Jetta TDI
NTDI,

Glad to hear of your mpg gain with the new nozzles. I have a feeling that when people such as myself and DustyB have a big drop-off in mileage over a period of time, it due to injectors/nozzles (barring any of the usual stuff).

DustyB,

Glad to hear of your power increase. I hope my results are the same after my cleaning.

jetta, 97,

I believe you and many others don't understand the mpg problems that people such as I and DustyB have.

I'm the original owner of my car. My driving habits are the same today as they were in 2003 when the car was purchased. I have records that show a decline in mpg starting in Fall of 2006. Since that time, I have gone from 44 mpg to 33 mpg. New TB kit, 2 new MAF's, change fuel filter every 10k, air filter every 10k, new glowplugs, new front wheel bearings, brakes on all 4 corners, adjusted IP and IQ settings, all the usual stuff......

Now gurus say the intake needs cleaned. Yeah, I don't doubt it, but I know it won't do one d**n thing to improve the mpg.

I'm begining to think that mpg problems such as mine , are due to a nozzel and/or injector problem.

df
 
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DustyB

Veteran Member
Joined
May 6, 2007
Location
Springfield, Oregon
TDI
2001 Jetta
dieselfuel said:
NTDI,

Glad to hear of your mpg gain with the new nozzles. I have a feeling that when people such as myself and DustyB have a big drop-off in mileage over a period of time, it due to injectors/nozzles (barring any of the usual stuff).

DustyB,

Glad to hear of your power increase. I hope my results are the same after my cleaning.

jetta, 97,

I believe you and many others don't understand the mpg problems that people such as I and DustyB have.

I'm the original owner of my car. My driving habits are the same today as they were in 2003 when the car was purchased. I have records that show a decline in mpg starting in Fall of 2006. Since that time, I have gone from 44 mpg to 33 mpg. New TB kit, 2 new MAF's, change fuel filter every 10k, air filter every 10k, new glowplugs, new front wheel bearings, brakes on all 4 corners, adjusted IP and IQ settings, all the usual stuff......

Now gurus say the intake needs cleaned. Yeah, I don't doubt it, but I know it won't do one d**n thing to improve the mpg.

I'm begining to think that mpg problems such as mine , are due to a nozzel and/or injector problem.

df
If you are planning on using the My Turbo Diesel walkthrough let me know there are a couple tips I'd add to the guide.
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
I don't think this is driving habit related, nor solely injectors, although fresh ones could help. The first thing you should do is get some VAG-COM timing data and run logs to check:

- MAF function
- N75 duty cycle
- Boost (actuator operation)
- Timing and timing advance

I suspect you have several issues that add up to poor economy. Your MAF may be OK, but not optimal. Your mechanical timing (crank, cam, and IP at TDC together) may be off, which could be a major contributor. And this won't be easily seen on VAG-COM, btw. You may be under-boosting, which doesn't help. And you can also check injector balance and see if they're out. B5 is probably good for keeping injectors pretty clean, but a can of diesel purge may help.

You could improve your driving habits, but I think you should be well into the 40s the way you're driving now if the car is set up and operating properly.

Getting a TDI just right is best done by a guru: you have several in OR that could help you out. It'll be worth the effort and expense.
 

Baldy_54

Veteran Member
Joined
Apr 9, 2007
Location
Maryland
TDI
2013 VW Passat SE, DSG
How about a fuel leak of the tank? My 2000 Jetta seems to have a fuel tank leak when the tank is full. Will check closer when warm weather comes. Leak is gone with 3/4 fill.
 

jetta 97

Vendor
Joined
Dec 25, 2008
Location
Dallas (McKinney) ,TX ,USA
TDI
2 X Jatta MK5 2006
dieselfuel said:
NTDI,



jetta, 97,

I believe you and many others don't understand the mpg problems that people such as I and DustyB have.

I'm the original owner of my car. My driving habits are the same today as they were in 2003 when the car was purchased. I have records that show a decline in mpg starting in Fall of 2006. Since that time, I have gone from 44 mpg to 33 mpg. New TB kit, 2 new MAF's, change fuel filter every 10k, air filter every 10k, new glowplugs, new front wheel bearings, brakes on all 4 corners, adjusted IP and IQ settings, all the usual stuff......

Now gurus say the intake needs cleaned. Yeah, I don't doubt it, but I know it won't do one d**n thing to improve the mpg.

I'm begining to think that mpg problems such as mine , are due to a nozzel and/or injector problem.

df
I do understand all about that. I have been working on cars 18 years and you don't have to tell me how that works. I am not saying injectors will not drop MPG. I had bad injectors on my car and still was getting 35MPG. When I put sprint 520 with out calibration it went up to 37 . When I did calibrate them and clean intake it went up to 42 city and 48 hwy. But this is summer time. Winter time I have drop about 5-7 MPG and that is normal.I went to San Antonio,TX 2 months ago and it was 35-40 F outside with 10 miles north-west wind(wind was blowing kind in to me) and had 43 mpg hwy. On way back fill up at same gas station (Valero) and had 45 mpg hwy. So you can see millage was not same. It was because of wind blowing in car. Also in Winter Engine need more time to worm up and fuel temp. is very low . In summer time fuel temp. when I check my graph it will get up to 190 F but winter time won't pass 120 F . If you know this ,this will drop MPG as well. Because ECU regulate fuel delivery from reading both temperatures (engine and fuel).
Also I newer get same MPG in city , it will depend of traffic . It will go in summer time for 38-42.

I have friends they driving 18 wheelers and they told me when they drive in Oregon ,Washington,Wyoming states because of strong winds truck with same loads will drop MPG from 7 MPG to 4.5MPG. If you do math That is about 35% less then normal.

One more reason to tell you it my be normal. I had Beetle 2001 with auto trany.
And my wife was getting 29-32 in city so I thought It my be something wrong.So i took car fill it up and drive 200 miles on 100% hwy. Fill it up back and boom. 44 MPG like spec. said. But my wife will run car every morning 5 min at idle and she was driving only streets ,lot of traffic stop and go did cause drop in MPG.

All I am saying in winter time in not right way to check your MPG.And also city driving is not right way to check MPG.
Wait till summer check you millage on 100% hwy driving and see.If you have less then 47 MPG then something is wrong. If you have around 47 MPG then there is no problem.
 

Souzafone

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Joined
Nov 4, 2004
Location
Freetown,Ma.
TDI
'99 Jetta A4, Whitish
jetta said:
I have friends they driving 18 wheelers and they told me when they drive in Oregon ,Washington,Wyoming states because of strong winds truck with same loads will drop MPG from 7 MPG to 4.5MPG. If you do math That is about 35% less then normal.

So you take a 35% hit in mpg driving through Oregon, Washington, and Wyoming?
 

Geomorph

Veteran Member
Joined
Oct 17, 2007
Location
Sacramento, CA
TDI
2005 Golf and 2002 NB
How's your thermostat and tires? I went through this with my ALH (which is an automatic); couldn't get above 37 mpg on the highway doing 60. I cleaned intake, egr, intercooler, new MAF, diesel purge. None of this seemed to make a difference. I got a scangauge and found that my car wasn't getting above 163F. So I changed the thermostat and now its 190F. I got new tires at the same time. The ones on the back were very cupped (previous owner neglect) and started getting 43-44 mpg on the highway. I'm not sure if it was the thermostat or tires that made the biggest diffence, but one or both worked for me.
 
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