any simple changes I am missing to improve MPG?

ColdStartTDI

Veteran Member
Joined
May 18, 2010
Location
Wisconsin
TDI
2002 Jetta TDI
I would like to get the best MPG on my 2002 Jetta TDI. Last tank I got 52 MPG. I would like to know if I am missing something. This site is great but sometimes hard to find everything simple to do to improve millage.

So far my changes:

Cleaned snow screen.
Clean air and fuel filter
Recent intake cleaning (professional)
Replace bad MAF
tires Altimax HP inflated to 40psi
Amsoil full synthetic oil
easy driving habits

I use BP gas but it is hard to know if it is Amoco station. I am thinking about getting a SGII but not sure if it is worth the cost?

I know there are expensive mods like chips and such but most on this site do not recommend for practical increases in millage. Are there any more simple sensors or filters cleanings I should be aware of? Is the amsoil Ea air filter worth getting?

Any other suggestions are welcome. Thanks for all the help?
 

Souzafone

Veteran Member
Joined
Nov 4, 2004
Location
Freetown,Ma.
TDI
'99 Jetta A4, Whitish
Timing should be in upper portion of graph via VCDS, a good fuel additive definitely won't hurt. Consider ditching the snow screen and using the cold climate air filter element. On a standard transmission you have coolant glow plugs, they shut off 2400 rpms, stay below that until the engine is warm and in theory it will warm up sooner, decreasing fuel use. I'm not familiar with your tires but I would consider going up to 90% of recommended max pressure only for a one tank effort, otherwise I'd stay at proper inflation. Use A/C only at highway speeds when possible, make sure nothing is hanging loose under the car. Good luck.
 

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
ColdStartTDI said:
I would like to get the best MPG on my 2002 Jetta TDI. Last tank I got 52 MPG. I would like to know if I am missing something. This site is great but sometimes hard to find everything simple to do to improve millage.

So far my changes:

Cleaned snow screen.
Clean air and fuel filter
Recent intake cleaning (professional)
Replace bad MAF
tires Altimax HP inflated to 40psi
Amsoil full synthetic oil
easy driving habits

I use BP gas but it is hard to know if it is Amoco station. I am thinking about getting a SGII but not sure if it is worth the cost?

I know there are expensive mods like chips and such but most on this site do not recommend for practical increases in millage. Are there any more simple sensors or filters cleanings I should be aware of? Is the amsoil Ea air filter worth getting?

Any other suggestions are welcome. Thanks for all the help?
My question to you is what does (your) easy driving habits mean in light of your (understanding of) oem VW owners manual technical page max torque rpm range and max hp rpm? This is potentially the most important and the greater % reasons of getting "better" fuel mileage.

I am assuming you have the 5 speed manual transmission.

The key is to put as many as the factors on your side as possilble.

I would (actually I do) clean the snorkle screen on some cycle, i.e., 5,000 miles.

Do NOT clean the air filter !! In fact, the best is once you seal the air filter in the air box; do NOT break open the seal !!!!!!! You can easily inspect both the clean side and dirty side of the air filter by removing the intact box. So do not remove for 80,000 to 100,000 miles (oemVW recommended change cycle is 40,000 miles) I actually remove the intact box (not breaking the seal) and empty the dirty side of the air box. Predictably, there is ALWAYS some quantity of silicon on the dirty side.

I understand the General tires are excellent. If it is a 51 psi max side wall pressure tire, you are running 78% of max sidewall pressure. I run 85% of 44/51 max side walll pressure tires, i.e., 37/38 psi/ 43/44 psi. To me it is a good starting point: ...adjust accordingly. One goal of mine was to have good fuel mileage, good handling and a shot at getting 112,300 miles from 3rd rate tires. You might not have the same goals.

Amsoil (if you are running the so called "correct" oil) is a very good 5w40 oil. It can be vilified for a host of reasons but to my mind, it is a very well crafted oil. I personally run Delvac 5w40, aka M1 5w40 TDT.

Incidently we get a range of 48-52 in rolling parking lot traffic (27 miles one way) On the road while I am ok with 48 mpg (584 miles, 12.1 gals, in 6.25 hours) 59 mpg @ 75 mph with bursts to 80/85 mph is alright too. We really do not try to get better fuel mileage, aka use hyper miling techniques. The key is know and apply the oem VW owners manual technical page.
 
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ColdStartTDI

Veteran Member
Joined
May 18, 2010
Location
Wisconsin
TDI
2002 Jetta TDI
ruking said:
My question to you is what does (your) easy driving habits mean in light of your (understanding of) oem VW owners manual technical page max torque rpm range and max hp rpm? This is potentially the most important and the greater % reasons of getting "better" fuel mileage.

I am assuming you have the 5 speed manual transmission.

The key is to put as many as the factors on your side as possilble.

I would (actually I do) clean the snorkle screen on some cycle, i.e., 5,000 miles.

Do NOT clean the air filter !! In fact, the best is once you seal the air filter in the air box; do NOT break open the seal !!!!!!! You can easily inspect both the clean side and dirty side of the air filter by removing the intact box. So do not remove for 80,000 to 100,000 miles (oemVW recommended change cycle is 40,000 miles) I actually remove the intact box (not breaking the seal) and empty the dirty side of the air box. Predictably, there is ALWAYS some quantity of silicon on the dirty side.

I understand the General tires are excellent. If it is a 51 psi max side wall pressure tire, you are running 78% of max sidewall pressure. I run 85% of 44/51 max side walll pressure tires, i.e., 37/38 psi/ 43/44 psi. To me it is a good starting point: ...adjust accordingly. One goal of mine was to have good fuel mileage, good handling and a shot at getting 112,300 miles from 3rd rate tires. You might not have the same goals.

Amsoil (if you are running the so called "correct" oil) is a very good 5w40 oil. It can be vilified for a host of reasons but to my mind, it is a very well crafted oil. I personally run Delvac 5w40, aka M1 5w40 TDT.

Incidently we get a range of 48-52 in rolling parking lot traffic (27 miles one way) On the road while I am ok with 48 mpg (584 miles, 12.1 gals, in 6.25 hours) 59 mpg @ 75 mph with bursts to 80/85 mph is alright too. We really do not try to get better fuel mileage, aka use hyper miling techniques. The key is know and apply the oem VW owners manual technical page.
Thanks Just the information I was looking for. Sorry about the confusion I have a clean air and fuel filter. :D It is a 5 speed. I will try to find out what a snorkle screen is and clean it.

I have really liked these new tires. I took the recommendation from tirerack.com and tried these instead the crap tires I usually got from tiresplus. I am very happy with them. In the snow they are exceptional and the rain they are great as well. They do have a 51 max psi. I will inflate them to 44. Thanks

I probably have a lot to learn about the best driving technique for best millage. I was hoping the SGII would help with that.

I used the Amsoil European Car formula 5W-40. When I started the car after the oil change in 1 min. the car lifters seemed to make less noise. In about 2 min. the car was making less engine noise over all. I did seem to get slightly better millage with that oil, which surprised me. I tried the oil from recommendation on a chain saw site. I am convinced it is better than the last synthetic oil I have used.

Not sure what hyper milling is but I am going to look it up.

Thanks for your help. It has been very enlightening.
 

Joe_Meehan

Top Post Dawg
Joined
Sep 3, 2005
Location
Ohio USA
TDI
NB TDI, 2002.5, Silver
ruking said:
... Do NOT clean the air filter !! In fact, the best is once you seal the air filter in the air box; do NOT break open the seal !!!!!!! You can easily inspect both the clean side and dirty side of the air filter by removing the intact box....
I certainly understand not cleaning the air filter* , but why not just replace it at 40 - 50,000 miles?

I might add that I am not all that keen or assuming that I can tell the condition of an air filter just by looking at it.


* The seals are not always reliable if reused.
 

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
Timing is a critical factor in achieving maximum economy. Cam, crank, and IP must all be at TDC at exactly the same time. A slight deviation will affect economy. And as others have noted, timing should be set to 60-70 on the VAG-COM graph, but only after static timing is spot on.

And new nozzles will probably help you at this point.
 

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
Again your owners manual technical page is potentially the place that will give you the best yield. (03 TDI) shows max torque to be delivered at a range of rpm 1,750 to 2,250. This in addition corresponds to the most efficient engine operation. So the short story is for most efficient engine operation consistent with "best" mpg: 1,750 rpm. For most efficient engine operation consistent with GOOD mpg, albeit you knowing take a "hit", 2,250 rpm. The sweet spot range is between 1750 rpm and 3500 rpm. Much beyond 3,000 however and you tend to induce slightly more wear with not much bang for the buck. In addition at 3,000 rpms.. well you can tell me what speeds you are traveling @. In this country it is probably against the law.
 

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
Joe_Meehan said:
I certainly understand not cleaning the air filter* , but why not just replace it at 40 - 50,000 miles?

I might add that I am not all that keen or assuming that I can tell the condition of an air filter just by looking at it.


* The seals are not always reliable if reused.
This is certainly a good question Joe. I certainly would not fault someone who changes the air filter @ 40,000 miles, the VW recommended interval.

That is why I never really "look" at it. In other words, if I see it is "dirty" (it is designed to be that way given its intended use) I do not instinctively change the filter so it has a "CLEAN" filter.

The primary reason is a tad counterintuitive. It is simply: "slightly" (defined as not near full restriction) used filters filter...better. The question which is ALWAYS shrouded in "reasonable to catastrophic" doubt is at what point does constriction affect performance parameters? Probably more important is how much constriction REALLY affects performance. This is very easy to verify as Drivibirewire has recommend the catepillar brand air filter gauge. ANYONE can do a visual!!!. A side issue is not many folks (extreme minority will, MASSIVE majority will NOT) will buy this gauge. Also VW has design specifications (just like 30,000 miles oil filters, which almost every one ignores. Shoot I even change the oil filter out @ 25,000 miles) @ 100,000 miles intervals.
 
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Joe_Meehan

Top Post Dawg
Joined
Sep 3, 2005
Location
Ohio USA
TDI
NB TDI, 2002.5, Silver
ruking said:
This is certainly a good question Joe. I certainly would not fault someone who changes the air filter @ ....
A well written and thought out reply. IMO.
 

ColdStartTDI

Veteran Member
Joined
May 18, 2010
Location
Wisconsin
TDI
2002 Jetta TDI
Oil filter change.

I look at it this way. I could change my underwear every 7 showers before anyone would notice but why not change your underwear with each shower. :D

I just assumed each oil change you change the oil filter. I know the oil filter might have more life left in it but why not change it since it is very inexpensive?

I think I am changing the air filter probably too soon. I was changing it once a year or about 20-25 kmiles.
 

jettawreck

Top Post Dawg
Joined
Aug 2, 2004
Location
Northern Minnesota-55744
TDI
2001 Jetta and 2003 Jetta
ColdStartTDI said:
Oil filter change.

I look at it this way. I could change my underwear every 7 showers before anyone would notice but why not change your underwear with each shower. :D

I just assumed each oil change you change the oil filter. I know the oil filter might have more life left in it but why not change it since it is very inexpensive?

I think I am changing the air filter probably too soon. I was changing it once a year or about 20-25 kmiles.
Changing your air filter "too early" won't hurt anything, but probably won't help much either, and in the economics of it will most likely not save more $$ than spent on extra filters.
Oil filters: OEM type are designed to go for much longer than the 10K oil change interval. I actually change mine every other oil change. Most will disagree, but the filter is made to trap particles and will never clog w/particles w/i 20K (or longer) unless something internally goes very wrong-in which case you have something else to worry about. Go with what you are comfortable with. Many cann't accept/bring themselves to even 10K oil change intervals due to years of advertising propaganda/habit and conventional oil use in gassers.
Looks like you've covered the maintainance stuff. You haven't addressed the timing suggestions/recommendations, so I assume you haven't explored that area yet. It is something that can increase your MPGs and doesn't cost anything.
Depending on miles on your vehicle, new nozzles may help (bigger nozzles don't always mean less mileage) but again, payback on them may not be realized for a LONG time, unless the current ones are wore (most likely not) or you would just like a performance and economy bump. Sprint 520 make for a mild power and MPG increase in my experience-your results, and other's, may and will vary.
ScanGauge is a great tool. Don't know if it will ever pay for itself, but I really like mine and am looking to buy a second one for the other TDI.
 
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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
ColdStartTDI said:
Oil filter change.

I look at it this way. I could change my underwear every 7 showers before anyone would notice but why not change your underwear with each shower. :D

I just assumed each oil change you change the oil filter. I know the oil filter might have more life left in it but why not change it since it is very inexpensive?

I think I am changing the air filter probably too soon. I was changing it once a year or about 20-25 kmiles.
Where do you buy underwear that is designed to filter synthetic oil for 30,000 miles????:p

My thought is once one has the information, one can do what one has to do. Along with that, it is hard to have an "economy" car when one does not take advantage of the designed parameters in ...economy.

As a sidebar: another (small but large) thing VW got right was the specification for 30,000 miles oil filter. There can be a whole commentary on this and for many different levels of meaning and application.

Even Honda (Civic) uses (recommended) 10,000 miles OCI's AND 20,000 miles oil FILTER changes. Of course most dealers try to get you to buy that at 2/4 times the rate 4 to 7 times the rate for the oil filter. I am clearing the soap box now.....

To give a visual on the "air filter service indicator", Catepillar product, http://www.cat.com/cda/files/1386243/7/PEHP9013-03.pdf
 
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uscgbeachbum

Well-known member
Joined
Apr 24, 2010
Location
Austin
TDI
2010 JSW DSG
ruking said:
Incidently we get a range of 48-52 in rolling parking lot traffic (27 miles one way) On the road while I am ok with 48 mpg (584 miles, 12.1 gals, in 6.25 hours) 59 mpg @ 75 mph with bursts to 80/85 mph is alright too. We really do not try to get better fuel mileage, aka use hyper miling techniques. The key is know and apply the oem VW owners manual technical page.
Ruking...can you elaborate on "rolling parking lot traffic"? I've only had my 2010 JSW for a month and a half now, but I can't get over 40 mpg at 70 mph on flat terrain. I'm the guy that accelerates super slow to keep the RPM under 2k. I came from a 2006 Civic that had a combined 34 mpg so I was hoping to get better mileage out of the JSW. The Civic got right at 33 mpg at 82 mph. Your 59 mpg at 75 mph would be dreamy.
 

1tdi

Veteran Member
Joined
Mar 21, 2004
Location
CT
TDI
Jetta 99.5 Black
uscgbeachbum said:
Ruking...can you elaborate on "rolling parking lot traffic"? I've only had my 2010 JSW for a month and a half now, but I can't get over 40 mpg at 70 mph on flat terrain. I'm the guy that accelerates super slow to keep the RPM under 2k. I came from a 2006 Civic that had a combined 34 mpg so I was hoping to get better mileage out of the JSW. The Civic got right at 33 mpg at 82 mph. Your 59 mpg at 75 mph would be dreamy.
Super slow accleration isnt good either, just drive normal, and your mpgs should reflect it. You could always chip it, and if a taller 6th gear is available you could install one.
 

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
uscgbeachbum said:
Ruking...can you elaborate on "rolling parking lot traffic"? I've only had my 2010 JSW for a month and a half now, but I can't get over 40 mpg at 70 mph on flat terrain. I'm the guy that accelerates super slow to keep the RPM under 2k. I came from a 2006 Civic that had a combined 34 mpg so I was hoping to get better mileage out of the JSW. The Civic got right at 33 mpg at 82 mph. Your 59 mpg at 75 mph would be dreamy.
Let's see, while I have driven in/through Austin, I am not as familar with traffic patterns as I am with say San Antonio, Dallas, Houston/Cypress. So I would guess a lot like Dallas and Houston. So 27 miles can take anywhere from 30 mins to 90 mins. In addition the road the car travels on is frequently noted as one of the worst in THE nation.

My closest model to yours is the 09 Jetta Sedan. SAME commute, we get a range of 40-47 mpg, 03 Jetta 48-52 mpg, 04 Civic 38-42 mpg.

Their are real performance differences between the Civic/TDI. Actually BOTH cars do best under brisker acceleration. The TDI benefits from slightly more aggressive driving. You do tend to get better mpg under a slight load and letting the torque take you to the next shift rather than revving without a slight load.
 
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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
uscgbeachbum said:
Ruking...can you elaborate on "rolling parking lot traffic"? I've only had my 2010 JSW for a month and a half now, but I can't get over 40 mpg at 70 mph on flat terrain. I'm the guy that accelerates super slow to keep the RPM under 2k. I came from a 2006 Civic that had a combined 34 mpg so I was hoping to get better mileage out of the JSW. The Civic got right at 33 mpg at 82 mph. Your 59 mpg at 75 mph would be dreamy.
Drive it harder. It needs full boost and higher revs to break in. And don't expect your best fuel economy for some time. My TDI really hit its fuel economy stride at 60K.

I followed DBW's break in procedure on my '06, and I never got great mileage with it until I sold it with 19K on it. Sootman has done much better, reporting 45 MPG in the car fully loaded (4 people and luggage) going 75-80 with the A/C on. That's a big jump from the 40 I was getting in an empty car when it was new.

Be patient, and don't baby it. Diesels don't like that.
 

ColdStartTDI

Veteran Member
Joined
May 18, 2010
Location
Wisconsin
TDI
2002 Jetta TDI
jettawreck said:
Changing your air filter "too early" won't hurt anything, but probably won't help much either, and in the economics of it will most likely not save more $$ than spent on extra filters.
Oil filters: OEM type are designed to go for much longer than the 10K oil change interval. I actually change mine every other oil change. Most will disagree, but the filter is made to trap particles and will never clog w/particles w/i 20K (or longer) unless something internally goes very wrong-in which case you have something else to worry about. Go with what you are comfortable with. Many cann't accept/bring themselves to even 10K oil change intervals due to years of advertising propaganda/habit and conventional oil use in gassers.
Looks like you've covered the maintainance stuff. You haven't addressed the timing suggestions/recommendations, so I assume you haven't explored that area yet. It is something that can increase your MPGs and doesn't cost anything.
Depending on miles on your vehicle, new nozzles may help (bigger nozzles don't always mean less mileage) but again, payback on them may not be realized for a LONG time, unless the current ones are wore (most likely not) or you would just like a performance and economy bump. Sprint 520 make for a mild power and MPG increase in my experience-your results, and other's, may and will vary.
ScanGauge is a great tool. Don't know if it will ever pay for itself, but I really like mine and am looking to buy a second one for the other TDI.
Thanks for the filter info. I did not know the filters were designed to filter so long. Is it the surface area? The last filter I used was a Mann.

I am a little nervous about the timing changes. I have a great mechanic that worked on VW for 20 years at the dealer and is now on his own. I might ask him about it when I take it in next time.

How much are bigger nozzles and how much gain can you expect?
Again thanks for the help.
 

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
Experience at a dealer is not necessarily seen as good in the TDI world. Dealers see relatively few of these cars and don't necessarily do things right, as you'll read here.

Don't know where you are in WI, but JasonTDI is in Madison and one of the best TDI mechanics extant. Send him a PM here if you want to learn more.
 
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