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General Information => General => Topic started by: stewardc on February 27, 2007, 11:21:34 am

Title: Best Fuel Mileage ???
Post by: stewardc on February 27, 2007, 11:21:34 am
There's an old guy, like myself, in BC who claims he's getting 100mpg from a turbodiesel Rabbit :roll: and is shooting for 120mpg.
What's the best you've accomplished?
Title: Best Fuel Mileage ???
Post by: dieselsnowmobile on February 27, 2007, 11:39:23 am
Best = 47 mpg (summer only)
Worst = 32 mpg (winter city driving and winter 40+ mph head wind)
Average = 40

I have always found I get better mileage in the summer.  I am still not for sure why.
Title: Best Fuel Mileage ???
Post by: Mark(The Miser)UK on February 27, 2007, 01:29:29 pm
DC if you re-read his notes you'll find he has only actuallyattained 70mpg imp and is suggesting we may reach 100mpg; he only suggests 120 as a goal  :shock:
I have reached 62mpg imp in a 'Q' on a 250 mile run (60- 65mph + a bit of 70mph+)
Title: Best Fuel Mileage ???
Post by: stewardc on February 27, 2007, 01:39:28 pm
Thatr's not what others on the site are saying and it definitely isn't what he's insinuating, but he is a wiley old cuss. He's hard to nail down. He insinuates he's got 100mpg and is going for 120.
Really, though, all that "hillbilly tuning" super-lean talk and all he got was 70mpg? I can do that on a good day with no tuning at all.
Title: Best Fuel Mileage ???
Post by: Mark(The Miser)UK on February 27, 2007, 02:01:14 pm
I'm inclined to agree he does flit like a butterfly :wink:  Apparently a world survey put the Scandinavians at the top of the happiness tree...
My goal is to attain 80mpg imp in a 'Q'
Title: Best Fuel Mileage ???
Post by: RabbitJockey on February 27, 2007, 02:34:37 pm
quatums do great mileage despite being heavier, the one guy i know has had quite a few of them and has nothing but but words for them.  i think a vnt 1.6 in a mk2 scirocco would make it easily possible to get into the 70mpg range.  the mk2 sciroccos are extremely aerodynamic.  i talked to a guy at h20 this summer that had an 8v scirocco that he is running on megasquirt, not even tuned properly, he gets 40mpg and thats with the 4k close ratio tranny that they came with.  insane.
Title: Best Fuel Mileage ???
Post by: burn_your_money on February 27, 2007, 07:39:04 pm
I don't keep track of mileage in the winter, it's depressing. I recorded 4 tanks before winter and best was 44.6MPG

I want to get 1200 a tank consistently. That's my goal for the summer. I'll need to do a compression test first and see if my engine is up to it
Title: Best Fuel Mileage ???
Post by: Jetta Fan on February 28, 2007, 06:23:09 am
DC, I was getting around 53-55mpg befor ethe cold weather hit.
Title: Best Fuel Mileage ???
Post by: AdAm84 on February 28, 2007, 06:43:03 am
my last tank was 40 mpg with a half turn on the fuel screw. my first tank on the untouched pump was 35, but it had also been sitting for like 10 years prior to me buying it. i can't complian. my wrangler only got 15 mpg :x
Title: Best Fuel Mileage ???
Post by: 95gltd on February 28, 2007, 11:51:33 am
Quote from: Jetta Fan
DC, I was getting around 53-55mpg befor ethe cold weather hit.


is that with your 97 1.9td?
Title: Best Fuel Mileage ???
Post by: Jetta Fan on March 01, 2007, 06:13:14 am
Yes, that's with my 97 Jetta 1.9TD. Why?

Now mind you.....that's driving it conservatively (shifting at about 2500, staying at 100 km/h or 60mph on the highway etc). Harder driving (shifting over 3000 and doing 70mph on the highway) drops it to 50-52 mpg.
Title: Best Fuel Mileage ???
Post by: addautomotive on March 01, 2007, 03:54:32 pm
Jeeze. I'm lucky to average 40mpg in my 1.9TD, and I still haven't beat 35 mpg in my sammy.
Title: Best Fuel Mileage ???
Post by: Benjamin on March 02, 2007, 04:27:38 am
Quote from: addautomotive
Jeeze. I'm lucky to average 40mpg in my 1.9TD, and I still haven't beat 35 mpg in my sammy.


yeah, i'm glad to read i'm not the only one, i was allready searching for whats wrong with my car  :P

Greetz, Benjamin
Title: Best Fuel Mileage ???
Post by: Patrick on March 04, 2007, 06:30:58 am
92 Jetta 1.9TD/k14, tall gears, about 47 mpg imperial in the summer, less on winter fuel. Exhaust is stright through, 2", no mufflers or resonators.

92Jetta 1.6TD/k24 standard gears, about 50 mpg imperial summer, less in winter. Factory toilet bowl, and full exhaust. Compression last fall about 420 across all 4 holes. Timing at .42.......

Both cars running lots of air pressure, no air conditioning.

Can't seem to get any better..........
Title: Best Fuel Mileage ???
Post by: 84Q on March 04, 2007, 10:06:14 am
i never get that kind of mileage out of my quantum...i'm consistently around 35mpg...no mods...any suggestions to help squeeze out some more mpg's?
Title: Best Fuel Mileage ???
Post by: Mark(The Miser)UK on March 04, 2007, 02:09:55 pm
Quote from: 84Q
i never get that kind of mileage out of my quantum...i'm consistently around 35mpg...no mods...any suggestions to help squeeze out some more mpg's?


Ideas in order of priority assuming injectors OK

1) Set timing exactly... wedge cam slop up with feeler gauges. Set pump to 1mm.

2) Use the 2" exhaust system from a 5 ganger gasser. Use a straight pipe for the snaked centre piece if you can find it.

3 ) Lift lid off spaceship and lean diaphragm. Drive and then gradually re-adjust until car responds sufficiently well for your driving style so that you don't have to hammer the accelerator to pass trucks...

4) Consider a different air filter...
Title: Best Fuel Mileage ???
Post by: Mark(The Miser)UK on March 04, 2007, 02:15:21 pm
Quote from: Patrick
92 Jetta 1.9TD/k14, tall gears, about 47 mpg imperial in the summer, less on winter fuel. Exhaust is stright through, 2", no mufflers or resonators.

92Jetta 1.6TD/k24 standard gears, about 50 mpg imperial summer, less in winter. Factory toilet bowl, and full exhaust. Compression last fall about 420 across all 4 holes. Timing at .42.......

Both cars running lots of air pressure, no air conditioning.

Can't seem to get any better..........
[/size]
Do you have any data for the 1.9 with a smaller exhaust?
Are these 'bests' or average 'mpg's
Title: Best Fuel Mileage ???
Post by: aidan on March 05, 2007, 01:28:28 pm
My first tank gave me 57mpg (UK), that was about 590 miles to about £38 (around 89-90p per litre)
For roughly the same money i've had 500, 570 and a couple in between.

I'm extremely happy with that as I have come from a VR6, and that was about 350miles to £50


PS this is a 1991 J Golf GTD with 147k miles on it
Title: Best Fuel Mileage ???
Post by: Mark(The Miser)UK on March 05, 2007, 03:37:13 pm
Aidan this is the GTD I've just bought for my mother-in-law.
PO was claiming about 40-50mpg 'biggals'
This seems a little poor to me. The car as you can see is pretty tidy. I suspect that the car is detuned as it is a little sluggish at low revs...

http://img110.imageshack.us/my.php?image=mygtdyo5.jpg
Title: Best Fuel Mileage ???
Post by: aidan on March 05, 2007, 03:53:16 pm
It looks like mine should, add a bent bumper, rust patches and slightly more pink paintwork and it would be mine as it is now!

Most of my miles are at around 65 on the motorway, around 50 miles per day, with around 10-15 round town with no queues, so generally quite hard on it. I've only had it about 5-6 weeks but done around 2500 miles on it.

I find it is sluggish at low revs to be honest, judders a bit if your not around 1800 or above. Not bad otherwise
Title: Best Fuel Mileage ???
Post by: Mark(The Miser)UK on March 06, 2007, 05:56:42 am
Quote from: aidan

I find it is sluggish at low revs to be honest, judders a bit if your not around 1800 or above. Not bad otherwise


Just went out and lifted the lid on the spaceship... Boost was set to a little below half way round (I'm talking the offset cone here) as is factory [should be].
 Note the position of the little dimple on the black diaphragm.  Look at the trace left by the lever as it follows the tapered cone rotate till maximum machining/offset is facing lever. Replace and go for a spin. If smoking then perhaps back off towards first position.  If not enough power then it needs to be the 'collered' fuel screw in a little...
For me there  is now still no smoking and the lag has all but disappeared.

Just noticed that there is a slight oil leak from the head gasket. May have been there for a while... Coolant slightly low so I'll keep an eye on it. Didn't check it 80 miles ago. Duhh  :roll:  
As long as there are no other problems :shock:

 Granny is now commiting herself to the car by transferring her insurance tomorrow. :cry:
Title: Best Fuel Mileage ???
Post by: aidan on March 06, 2007, 03:44:55 pm
I intend to start tampering with the pump and boost this weekend as a boost gauge is in the post.

Funny you should mention the head gasket, i've got hard smoky starting (gets better the more I cycle the plugs) and the expansion tank was still pressurised long after switching off.
I'm hoping the new blue tank cap and reseating the injectors (very slight leak at the head) may solve
Title: Best Fuel Mileage ???
Post by: Mark(The Miser)UK on March 06, 2007, 04:48:54 pm
Best check for pressure is to crank over for a few seconds from cold and then listen for a psst when opening cap
Title: Best Fuel Mileage ???
Post by: aidan on March 07, 2007, 12:14:14 pm
Well I took that cap off just then, plenty of air escaping then.

Then put the cap back on, cranked for a few seconds, opened the cap and nothing. No overheating, no using oil or coolant, no sign of oil in the coolant or vice versa. Anyway, thats for the troubleshooting section I guess.

At the same time was going to have at go at lifting the lid as you did, well not one of my screwdrivers will loosen them screws! I should have another round somewhere with a larger head on it
Title: Best Fuel Mileage ???
Post by: 95gltd on March 07, 2007, 01:15:26 pm
Quote from: Jetta Fan
Yes, that's with my 97 Jetta 1.9TD. Why?

Now mind you.....that's driving it conservatively (shifting at about 2500, staying at 100 km/h or 60mph on the highway etc). Harder driving (shifting over 3000 and doing 70mph on the highway) drops it to 50-52 mpg.


I average 42mpg(imperial) in the winter and maybe 1 mpg better in the summer. Always shifting @ 2000rpm. Sometimes a little higher on a big hill never over 2600rpm. Tires blown up to correct pressure. New air filter/fuel filter,rebuilt turbo. I did see around 52pmg with my old 85 1.6 n/a diesel.

You must see around 1050km on a tank?

I need some help with my golf. I took it to the vw shop last fall to get the timeing on the pump set. Now i have to run with the handle out or at speed on the highway it skips like it goes from 4-3 cyls then back. I'm thinking my injectors might be bad. Would bad injectors cost over 5 mpg?
Title: Best Fuel Mileage ???
Post by: Mark(The Miser)UK on March 07, 2007, 01:59:35 pm
What does it idle like?
Title: Best Fuel Mileage ???
Post by: aidan on March 11, 2007, 10:17:53 am
Mark,
Just rotated the boost pin, though was a little confused by a few parts of your instructions.

The little dimple firstly, thats on the metal that surrounds the black diaphragm right, not on the diaphragm itself?
Trace, well don't know what you mean by trace.
Finally when you say lever I assume you were referring to the main 'throttle' lever for want of a better term?

Anyway, the maximum machined bit and dimple are facing the lever, or in line with the bottom left screw as you look at of the spaceship. Went for a spin and to be honest didn't feel any different.

Your quote;
Just went out and lifted the lid on the spaceship... Boost was set to a little below half way round (I'm talking the offset cone here) as is factory [should be].
Note the position of the little dimple on the black diaphragm. Look at the trace left by the lever as it follows the tapered cone rotate till maximum machining/offset is facing lever. Replace and go for a spin. If smoking then perhaps back off towards first position.
Title: Best Fuel Mileage ???
Post by: jtanguay on March 11, 2007, 11:01:40 am
Quote from: "95gltd"
Quote from: "Jetta Fan"
Yes, that's with my 97 Jetta 1.9TD. Why?

Now mind you.....that's driving it conservatively (shifting at about 2500, staying at 100 km/h or 60mph on the highway etc). Harder driving (shifting over 3000 and doing 70mph on the highway) drops it to 50-52 mpg.


I average 42mpg(imperial) in the winter and maybe 1 mpg better in the summer. Always shifting @ 2000rpm. Sometimes a little higher on a big hill never over 2600rpm. Tires blown up to correct pressure. New air filter/fuel filter,rebuilt turbo. I did see around 52pmg with my old 85 1.6 n/a diesel.

You must see around 1050km on a tank?

I need some help with my golf. I took it to the vw shop last fall to get the timeing on the pump set. Now i have to run with the handle out or at speed on the highway it skips like it goes from 4-3 cyls then back. I'm thinking my injectors might be bad. Would bad injectors cost over 5 mpg?


well it can cost you that, and some pistons maybe???  i had some work done on my car and the guy who did it said that my pistons were melting on the outer edges.. most likely from high egt's and bad injector spray pattern... but my glowplugs are fine! go figure.