Fuel economy . . .

[Guest]

How can I tell if I my 88' 944 non turbo is using the correct amount of fuel? How many miles to a tank should I expect to get just driving it conservatively? Has anyone tried any injector cleaner or fuel addative and had any improment on economy? I can put about £20 is and only see about 130 miles is this right?

 

[Fen]

I've not had a Lux, but that sounds about right. It costs £60+ to fill my Turbo with Optimax and cruising or taking it easy as on Sunday I get about 350 miles out of it. On track about 90.

 

[PRJ]

350miles a tank in your modded monstrosity??!!! I was punching the air the other week when I wangled 300 miles on a tank (circa £65). Do I have a fundamental problem do ya think (other than rightfootitus)?

By the way - for those of us whose fuel warning light doesn't go on (i.e. is broken), at what level does the light appear in relation to the orange line?

 

[colin129]

My S2 generally gives 28mpg in summer and 26mpg in winter, a quick calculation on Siddus74 figures comes out at about 26 (assuming 89p per litre) which seems round about right. On a long motorway run I get around 30/31, I have manged a little more than this on the continent as higher, sustained speeds are more easily attainable.

Generally about 420 miles on a tank, but can get close to 500 depending on how long I am prepared to play fuel light bingo. My biggest fill up was over 79 litres (the tank holds 80!) and 560 miles (32mpg), but I was certainly sweating a bit when I got to the pump, although since it was in Luxembourg, I saved a small fortune.

I rekon about 2 1/2 gallons left when fuel light goes on, which does not appear until the needle is touching the orange bar.

 

[wizard]

I run a turbo so no point answering your question directly, although I've given up putting £10, £20 worth in as petrol prices are up and down in my area. One moment you pay 90p/Ltr then the next its 84.5p/Ltr. When you pay a higher price £20 doesn't seem to last so long. I now put in number of litres i.e 25 litres i.e 5 gallons or 45 Litres 9 gallons etc. This way I can estimate 80 - 100 miles.

 

[Mikie_gb]

34mpg driving on the open road 11mpg in town. And anything in between depending on its mood. Only use optimax which returns a 10% improvement in consumption (for what ever reason).

 

[colin129]

ORIGINAL: wizard

45 Litres 9 gallons etc.

That's 10 gallons...

 

[sawood12]

My fuel guage has no light at all on it - there is no see-through screen so they must have been introduced after 1987. I usually fill up every time and will get around 350 miles before I fill up when the guage is just starting to enter the red which usually comes out to be around 62 - 65 litres which equates to about 25ish mpg. In the winter i'll get closer to 300 miles out of 62ish litres which equates to about 24mpg. Recently i've taken to squeezing more out of my tank by letting the air pocket escape as you fill the tank more after the first time the pump clicks off. You can usually get another £10 in there so i've not yet re-calibrated myself.

I reckon we do OK for fuel economy. I don't believe the marketted MPG figures against new cars. My dad can only break 30mpg in his TT if he really takes it easy and generally he averages 25 to 28 mpg per tank. And similarly I've a few mates with Golf TDI's who average 35MPG per tankfull and can only break 40mpg tank average if they are on a long motorway journey so 25mpg for an 18yr old performance car is pretty good I think. Spare a thought for 928 and 911 owners who are pleased with 18 mpg and delighted to break 20mpg unless they are really taking it easy.

 

[Fen]

Nope, the light came with the oval dash. My very early '86 Turbo had one. It doesn't light with the ignition lights as bulb check (very stupid IMO) so it's a lottery first time you try to see if it works. Get a can filled and drive until either it comes on or you run out is my suggestion. It doesn't light until you're most of the way through the red segment and I would be reasonably comfortable going up to 50 miles with it on so I rarely fill until it lights. I have done 53 or 57 or something with it on, and I have yet to run out. My car has the "open loop lean highway" setting turned on in the engine management (remember I have aftermarked standalone management so that isn't an option on anyone else's cars) which runs it quite lean (15:1 ish AFR) at a cruise but very quickly drops to 11's when the throttle opens. Before I turned that on it was lucky to do 240 on a tank.

 

[Fen]

By the way the reason I have never bought a Leon Cupra or Golf GTI turbo is mainly that VAG 1.8 20VT engine they share with the Audi Twat'sTransport, which is very poor on fuel economy as well as being very flat over 5,500 rpm.

 

[944Turbo]

My economy improved with mods, Dont know if I cant drive on boost for as long or wether the efficiency has improved but I now get 330+ to a tank driving hard, cruising in the 80 to 100 range (occasional bursts over) and using full throttle acceleration whenever safe.
Driving off boost I can get 400+ but I am not good at that.
Tony

 

[944Turbo]

Oh and agree with fen light is in oval dash cars but you have to get well into the orange line before it comes on. You can get a good way into the light section approx 2 or 3 line widths below the line without running out. One day I will take a can with me and find out how far.
Tony

 

[PRJ]

Oh ok - well perhaps my warning light isn't malfunctioning then. I thought I'd read on a previous thread that there was a bulb test via the ignition. I'll try and hold my nerve then and see if/when it comes on.

 

[Fen]

ORIGINAL: 944Turbo

My economy improved with mods, Dont know if I cant drive on boost for as long or wether the efficiency has improved but I now get 330+ to a tank driving hard, cruising in the 80 to 100 range (occasional bursts over) and using full throttle acceleration whenever safe.
Driving off boost I can get 400+ but I am not good at that.
Tony

I agree. When I had my first mods done so it was breathing better but running standard injectors (as it was the day you drove it, Paul) it would easily do over 400 to a tank.

 

[944Turbo]

And on trackdays mine is also truly awfull - Silverstone particularly less than 10mpg I reckon.
Tony

 

[Guest]

14mpg town and 30 on motorway, put 17 litres in other week lasted 55 miles, so not that good round town me thinks

 

[sawood12]

From memory the handbook states 44mpg at a steady 56mph although i've never tested this for real but if you work this out against the usual 62 ltrs I normally put in the tank it should be good for 600 miles!! Again I think that's optamistic marketting figures. I would exect at least 400 miles on a steady run up the motorway which is about 30mpg so anything more that 400 miles and your into the 30's.

 

[berg944]

When I purchased my turbo I got 34 mpg on the 250 miles home, at least the wife did as she refused to drive the van home!

Not as economical with me driving[]

Did go down to about 12-15 mpg the other week when a pipe came off the inter-cooler.

Any air leak from the turbo will cause overfueling, now an expert in such matters [8|] []

Mike[:'(]

 

[carlmthompson]

ORIGINAL: Fen

By the way the reason I have never bought a Leon Cupra or Golf GTI turbo is mainly that VAG 1.8 20VT engine they share with the Audi Twat'sTransport, which is very poor on fuel economy as well as being very flat over 5,500 rpm.

Yup, Passat 1.8T I had while being the best screwed together car I've had, was utterly dissapointing. Never mind Turbo lag, it felt like no Turbo. Poor average of 33MPG (mostly 75MPH on the motorway) put the nail in that coffin....

 

[PRJ]

ORIGINAL: 944Turbo

Oh and agree with fen light is in oval dash cars but you have to get well into the orange line before it comes on. You can get a good way into the light section approx 2 or 3 line widths below the line without running out. One day I will take a can with me and find out how far.
Tony

Literally just found out that my light does come on. It seemed to be on the orange line for ages before it appeared, but what a way to find out...

Just cruising back home on the A24 at 90ish, when something big and black shot past me (ooer). Plate was V8 AUD and guess it was an RS6 saloon (looked bigger than a 4), with aftermarket alloys, exhaust etc. He'd whistled past at 120mph I guess, but then slowed down until I caught up. I eventually decided to take the bait (I'm such a sheep) and floored it. Wondered what the orange light was on the dash and whilst looking down (very briefly) and realising it was the fuel guage (phew), saw an indicated 150mph. Fastest I've been in a car and Mr V8 didn't get away either. Easily kept station with him and he braked way earlier into the roundabout, to the point that my back-end got all squirmy as I avoided having to plough into the back of him. It's not big and it's not clever I know, but the road was clear of other traffic etc.. (aside from the bike that had joined the party!) and I now have a silly grin all over my face.