Improving gas mileage - Jetta 2.5

[BsickPassat]

Hey all,

I’m looking for some advice on the best ways to improve the gas mileage on my Jetta 2.5. It is a manual and I do try and shift before the tach hits 3000.

Besides putting in a K&N filter is there any other non-major work that I can do to the car to make it consume less?

See if a TDI belly pan fit. allows for smoother flow under the car

lower the car (smaller front area for drag)

keep the car in tune (air filter, plugs, etc).

Use good fuel, like Chevron, Shell, Texaco, etc.

use Low Rolling Resistance tires

[WDM1980]

Thanks for all the information guys.

So far I'm averaging 10.4 L / 100 KM (that's 22.6 mpg) - with a combo city / hwy; that's well worse than rate assumed by VW.

I guess it's time to consider a few minor mods to get that under control.

I will certainly look into a K+N filter and possibly a short ram intake.

Would chipping the car void the VW warranty (pre-owned warranty - 2 yrs, 40,000 km)? Which chip do you guys recommend? My local mechanic will have to be doing all the work as I don't have a space where I can work on this car (live in a condo).

In the future, I will look into better tires as I go to a lower-profile summer tire/wheel combo and probably lowering it to improve the ride / profile.

Thanks again - keep the advice coming!

[cweber]

Would chipping the car void the VW warranty (pre-owned warranty - 2 yrs, 40,000 km)?

Yes, chipping will void your CPO warranty. There are some chips that allow you to "lock" or to reset to factory (idea being that nobody will be able to tell it's been chipped), but to me, it's not worth it. I really want to chip my GTI, and it's going to be a long-ass wait until my warranty is up, but it's just not worth giving up that little safety net while I've still got it!

Somebody correct me if I'm wrong about some chips having a "lock" setting of some sort?

[thygreyt]

hold on.

"chipping" or flashing the car with new software DOES NOT VOIDS ANY WARRANTY.

Please search before saying such things.

[cweber]

hold on.

"chipping" or flashing the car with new software DOES NOT VOIDS ANY WARRANTY.

Please search before saying such things.

http://forums.vwvortex.com/showthread.php?3754005/page1

http://forums.vwvortex.com/showthrea...arranty+engine

http://www.goapr.com.au/support/chip_tuning_faqs.html

The gist of it to me seems to be that while technically the dealer cannot refuse to do warranty work unless the dealer can PROVE the chip is to blame in some way shape or form, you may still have a fight on your hands with some dealerships.

So, thank you for the correction - you are correct, TECHNICALLY it will not void your warranty. For me, it just isn't worth the fight with the dealership/bringing VWoA into things, but hey, to each his own! Thanks again for letting me know the real deal.

[thygreyt]

So, thank you for the correction - you are correct, TECHNICALLY it will not void your warranty. For me, it just isn't worth the fight with the dealership/bringing VWoA into things, but hey, to each his own! Thanks again for letting me know the real deal.

lol.
but then it comes out to the dealer. some dealers FIND the issue. while some other just blame it on any visble mods.

[K^2]

My 2007 Rabbit with 6 speed auto gives me between 26 to 32 mpg.
The 32mpg I averaged on highway doing steady 65 with no AC on.
I get 26 in the winter driving around the town. Summer with a light foot I would get up to 29mpg driving around.
Yes the car for its size has a horrible fuel economy. Germans don't have a clue how to build efficient gas engines. How come a larger Ford Fusion can get 34 on highway with comparable size engine? I have no clue why VW stuck that engine in that car. They don't have it in Europe. As usual VW always shoves inferior cars in the US market.

[KyleLaughs]

You got a stick right? Hop into neutral while going downhill or approaching a red light while youre still a good quarter mile out. Then get good at matching revs and hopping back into gear.

[JETTAMKV21]

I've gotten 36mpg in my stock 2010 jetta. almost all highway at an avg. speed of 75mph. drove from Poulsbo,WA to woodburn,OR (just south of portland)

It really all depends on how you drive and if it's highway or city.

[brianbgw]

I've gotten 36mpg in my stock 2010 jetta. almost all highway at an avg. speed of 75mph. drove from Poulsbo,WA to woodburn,OR (just south of portland)

It really all depends on how you drive and if it's highway or city.

You are aboslutley right. I drive a stock 2007 jetta 2.5 automatic and I have seen numbers as low as 17MPG and as high as 37 MPG. on the low end it is a bunch of drives from home to school or work (I live 2.5 miles from both) so the car is never warmed up. On the high end, after fresh oil change, new air filter, new spark plugs, and slightly over-pressured tires running premium fuel and setting cruise control exactly at 60MPH I have seen upwards of 37 MPG on the commute between Seattle and Bellingham. Whoever keeps saying that people are full of $%* should really try and think before speaking. Just beacause YOU arent capable of enough self restraint to go slow on the freeway doesn't mean that nobody else can. That being said, it is a rarity to get that kind of mileage, only under those specific conditions- usually I average around 20-25 MPG because I do so much cold city driving. Getting the best mileage means bringing every component of every system back up to brand new condition like it was when you got it after a pretty substantial break in period

[thygreyt]

I get 30 mpgs going at 70-75... My record is 430 in one tank, and i havent really tried to top it...

And we hwve said it many times, its more thn the car, its the driving style

Sent from my HTC Sensation 4G using Tapatalk

[tchilds]

dealers don't check for chips on 2.5 motor. nobody tunes these things like the GTI. they didn't even care when I brought my 2.5 in w/SRI on it for warranty work on a compressor, that I BROKE!!!! When I had my GTI, the same dealership told me they couldn't touch my car just looking out the window at it parked in the lot.

The dealer doesn't care what you do to a naturally aspirated car. NOTHING you can do to these N/A motors is going to cause the stress that a chipped GTI goes under. Turbo cars get chipped and max out their stock turbo, this is why dealerships don't work on them if they can get out of it.

If you bought it CPO, just tell them it came that way and you have no idea what they're talking about if they ask. It takes a very clever technician to diagnose an encrypted flash program, one that likely has more important things to worry about. That or it takes a moron to rev your car to 7500rpm and realize its chipped, which is technically not the proper way to diagnose it so they would not admit to doing this.

As far as fuel economy. you're not going to get it out of a 2.5L gas engine... DUH. I average 28mpg which is basically what my MK4 vr6 got. This 2.5 is NOT an economy motor!

[jtrujillo86]

About 15,000 miles ago I purchased a set of Bridgestone Ecopia all season tires and I've seen a nice increase in MPG. They perform just as good as my previous Bridgestone Potenza A/S tires, but I consistently see 32 MPG on the highway, doing 80 miles an hour. The best I had seen with the Potenzas was 28.

- Jeremy.

[Girevik82]

I honestly think this is a total waste of time and effort trying to get more gas mileage out of your rabbit. It has an engine that has some pep, its torquey, it is ment to be driven. I have a somewhat heavy foot and still get avg 23-24 mpg driving 75% on high way at about 70-75mph. If you are really so concerned about gas mileage than trade it in for the new TDI rabbit or another tdi or hybrid car. Otherwise it's just adding yourself a headache being anal to add another 1-3 mpg to your overall gas mileage. Enjoy the 2.5, drive it like it's ment to be driven .

[vetaldj]

Oh, those numbers you all wrote is looks like a dream for me...

My 08 Rabbit, stock has once 23mpg mostly highway but daily average is 18-19 mpg 50/50 city/ highway but constant stop and go on both... I was wondering if something wrong with it or it's something wrong with my foot ?

[boulbrokdrm]

bull no way you got 444 miles of a tank in with a 2.5. your like the only person in the world to report that many miles.

i once got 400 miles before my gas light popped on. 2007 rabbit 2.5 stock 5spd

did the math afterwards and it turned out to be 30mpg.

[goldenhalo]

I have a 2005.5 Jetta, 2.5L. Best mileage I have gotten so far, has been right under 29mpg. And I do drive mostly highway to and from work. Otherwise, I'm somewhere between 24-26 mpg. I don't try too crazy, but I do get on it every so often. It does help to not rev above 3k, that's for sure. My mileage improved after I replaced my plugs and cleaned out my system (Seafoam anyone?). But I dunno, it's a 5 cyl, I don't expect 30+, but I bet I could do it with nice long highway drives on a trip or such. My old Grand Am GT (2.4L 4 cyl 5-spd) used to get 32 mpg all the time around the city, but again, it was a 4 cyl.

On that note, I did just put on a new catback system, and was told my mileage would drop, so we'll see. I would like to do a cold air intake, I've heard that helps a little.

[MKVJET08]

I wish I was stock again after seeing y'all's numbers. I get 24 at best, all highway, driving like a grandma.

[konsole]

On my Rabbit I get about 26-27 mpg avg. and my low gas light comes on around 320-340 miles.

Start with the free options like reducing unneeded weight and drag, but consider that to yield anything more then 2-3 mpg improvement you need to do more drastic things that are either expensive, and cancel out the purpose of saving gas, or heavily modify your car.

Mid to upper 20's isnt bad but if gasoline rises another .50-1.00 and looks like its going to stay there for atleast a few years I would seriously consider a tiny car that gets upper 30's or more, providing it would be fairly close to an even trade in terms of car value. However a tiny car like a Smart Fortwo or Scion iq doesnt bother me because I rarely have other people in my car, I don't drive alot, and dont carry around alot. Going from 27 to 37 mpg will yield a $350 savings per year on gas for me if gas averages $4.50 which I think is very possible. Not worth it if gas averages less then that in the years upcoming and or if the replacement car is more expensive.

[v408w]

gas is 4.30 for 87 here

[MKVJET08]

gas is 4.30 for 87 here

Holy hell!

If it gets any higher people in CA are going to start hooking for gas money.

[v408w]

Yup where I normally get gas I am paying around 4.50 for premium

[shiva916]

I have been averaging in the high 20's since I bought this car almost 2 years ago and over the last 18k miles. I have only missed a few fill ups in my log, and I have averaged as high as 32mpg on a single tank and my low is around 24 or 25. I usually don't beat on the car at all. I have a 35 mile commute each day which is mainly non-congested back roads a small amount of highway. Just take off easy and don't romp on the gas, I normally shift between 2-2.5k maybe 3k (unless getting on the highway), and i typically go straight from 3rd -5th in normal driving (5 speed). I have had a Neuspeed P-Flow for about a year and half and put on a votex exhaust about a month ago.
While not the most fuel efficient car I don't think it's that bad.

[mbSandflea]

I'm now driving a 98 GLX that gets between 25-27 miles to the gallon depending on how I drive it. My wife drives the newer 07 Wolfsburg 2.5 and has gotten around 28 on it through two tanks. I can drive the GLX round trip 16 miles a day for a week on $20 worth and she drives the Wolfie about 50 miles roundtrip a day for a week with a fill up.

I'm completely content with the mileage we're getting out of both cars because both are an impressive gain over the $100 a week I was spending on gas driving my 2006 Dodge Dakota that averages 17 miles to the gallon.

[goldenhalo]

I have been averaging in the high 20's since I bought this car almost 2 years ago and over the last 18k miles. I have only missed a few fill ups in my log, and I have averaged as high as 32mpg on a single tank and my low is around 24 or 25. I usually don't beat on the car at all. I have a 35 mile commute each day which is mainly non-congested back roads a small amount of highway. Just take off easy and don't romp on the gas, I normally shift between 2-2.5k maybe 3k (unless getting on the highway), and i typically go straight from 3rd -5th in normal driving (5 speed). I have had a Neuspeed P-Flow for about a year and half and put on a votex exhaust about a month ago.
While not the most fuel efficient car I don't think it's that bad.

How do you feel about the P-Flow? I just put my Votex exhaust on last night, love it so far.

[VWMoparGuy425]

Weld up your combustion chamber, polish it, surface it -0.005, and dynotune it. fuel economy will get better I have done stuff like this before on previous builds.

http://forums.vwvortex.com/showthrea...and-MPG./page2

[magics5rip]

Weld up your combustion chamber, polish it, surface it -0.005, and dynotune it. fuel economy will get better I have done stuff like this before on previous builds.

http://forums.vwvortex.com/showthrea...and-MPG./page2

You are basically just increasing compression...could you not mill the head down a few thousandths and achieve the same result? Assuming there is no interference between valves/pistons...

[VWMoparGuy425]

You are basically just increasing compression...could you not mill the head down a few thousandths and achieve the same result? Assuming there is no interference between valves/pistons...

I just wanted to stay on the save side. I have had my fair share of bad luck. Just welded the quench pad because it didnt interfere with the deck height and P to V too much with only .005 shaved off. just really wanted to clean it up just in case there was any little warping.

[A1an]

My wife drives like a grandma and typically doesn't get more than 350 miles before the light comes on. Car in question is a Rabbit with a 5-speed with a roof rack.

[BIGJEFF64]

i need to change my plugs and air filter!!!!

[shiva916]

How do you feel about the P-Flow? I just put my Votex exhaust on last night, love it so far.

I actually like mine, that was my first mod (along with some smoked side markers lol) and have been very pleased with it. It was pretty easy to put on (took about 30 mins tops) and the sound is great. The only thing I find is slight buzz or rattle from it when the engine is at low revs under load (around 1k rpm) but it passes within 2-300 rpm.


A1an - try taking the roof rack off if you aren't using it all the time. I usually go at least 350 miles and re fill a bit before the gas light comes on. Racks tend to add a lot of drag to the car.

[tonsef]

I average about 29~30 mpg on my way to work, which is 15 miles away (with a 2.0t). I, stay in nuetral a lot of the time and use cruise control on the more flat sections of roads. also i'm not sure but according to some the tune will help your mpg, maybe a cai.

[fierostetz]

I actually like mine, that was my first mod (along with some smoked side markers lol) and have been very pleased with it. It was pretty easy to put on (took about 30 mins tops) and the sound is great. The only thing I find is slight buzz or rattle from it when the engine is at low revs under load (around 1k rpm) but it passes within 2-300 rpm.


A1an - try taking the roof rack off if you aren't using it all the time. I usually go at least 350 miles and re fill a bit before the gas light comes on. Racks tend to add a lot of drag to the car.

i feel like the filter that came with mine sucks; it was a TOTAL beast to fit on the end of the pipe - same for you?

I'm thinking about changing to a larger/better filter.

[vetaldj]

I also have bad milage but few fill ups I decided to try higher grade gas and I was suprised that my milage go up to 22-23 mpg from 17-18 mpg even though I have sticking caliper at the back and same driving routing as always.

I was using 87 grade but filled with 89. Back in mainland I always used 89 with ethanol for best result as well. It's no in my head as I calculate it after each fill up.

[thygreyt]

Hey all,

I’m looking for some advice on the best ways to improve the gas mileage on my Jetta 2.5. It is a manual and I do try and shift before the tach hits 3000.

Besides putting in a K&N filter is there any other non-major work that I can do to the car to make it consume less?

i get 28 mpgs on almost every tank.

3 key things:
-learn to drive in neutral
-maintenance is paramount
-mods help (sw, intake, etc)