A8 Parts Forum  

Go Back   A8 Parts Forum > A8 D2 > D2 - Fuel and Exhausts

D2 - Fuel and Exhausts Everything to do with getting fuel into the engine, and fumes back out again

Reply
 
Thread Tools Display Modes
  #11  
Old 25th April 2017, 09:03 PM
tonupkid's Avatar
tonupkid tonupkid is offline
Senior Member
 
Join Date: Feb 2009
Location: Inhabiting a house in a village, rural with lots of lovely roads
Posts: 1,872
Default

Quote:
Originally Posted by Goran View Post
Ainar you know everything about these cars.
You must have taken one apart and put it back together again.
Its good to know these things.
Agreed
__________________
A journey of a thousand+ (epic) miles, begins with a single step, (to the door of an 8). Lau Tzu
Reply With Quote
  #12  
Old 29th April 2017, 02:50 PM
Goran's Avatar
Goran Goran is offline
Senior Member
 
Join Date: Feb 2011
Posts: 1,968
Default

So I filled up to full tank today. I only managed to put 77.3l in and now I am a bit confused. Stopped straight after to VCDS the fuel level it shows 89l.
x + 4.5 + 77.3 = 89

If the fuel level sensors are to be trusted that means there were roughly 7 litres still in there when the range read zero and VCDS showed 0 litres.

Perhaps it is possible? Kind of reassuring, but also annoying, I assume I could have used at least another 3 of those litres without endangering the fuel pump?
Thats roughly another 15 miles!
Reply With Quote
  #13  
Old 29th April 2017, 02:56 PM
HPsauce HPsauce is online now
Senior Member
 
Join Date: Sep 2011
Location: About 250m from HS2!
Posts: 6,383
Default

I reckon, that on both my S8's there was usually about 2 gallons (9L) left in the tank when range was showing as zero.
__________________
2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation".
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
Reply With Quote
  #14  
Old 29th April 2017, 08:39 PM
Goran's Avatar
Goran Goran is offline
Senior Member
 
Join Date: Feb 2011
Posts: 1,968
Default

That sounds about right. I find it so strange that so much fuel is left when range and fuel sensor reads zero. Unless its needed to save the fuel pump, but why so much?
Reply With Quote
  #15  
Old 29th April 2017, 09:18 PM
paulrstaylor paulrstaylor is offline
Senior Member
 
Join Date: Jul 2010
Location: Manchester
Posts: 894
Default

Quote:
Originally Posted by Goran View Post
That sounds about right. I find it so strange that so much fuel is left when range and fuel sensor reads zero. Unless its needed to save the fuel pump, but why so much?
I only ever ran out once in my D3, I had done about 50 miles some of which were towing a trailer since the tank showed zero, and then it only ran out as I was going up hill!!!!! Started up when I put a gallon in that I had in the boot, probably the only time I got more than 90 litres in that fill!

There is a big margin for sure, and I suspect the tank and filler is marginally more than 90L also
Reply With Quote
  #16  
Old 29th April 2017, 11:27 PM
27litres's Avatar
27litres 27litres is offline
Senior Member
 
Join Date: Jan 2014
Location: Belgrave, Australia
Posts: 481
Default

Quote:
Originally Posted by paulrstaylor View Post
There is a big margin for sure, and I suspect the tank and filler is marginally more than 90L also
I reckon if you brim the tank and have good tank and sender seals in a D2, it has an extra 1 to 1.5 litres in the filling neck too. Probably similar in a D3. I doubt these are calculated in tank capacity....
__________________
Cheers

Marty


____________________
Current:
2001 Audi S8 - Brilliant Black with Black interior, C5 RS6 rims (whenever I actually put them on...), Solar Sunroof, Tinted side and rear glass, RNS-D, XCarLink, Bose, clunky old phone in arm rest!
2002 Audi S8 - Project
Replacement head coming arrived thanks to MJ
Silver with Black interior. All features as the '01, with the 'S' mode auto shifter. Dodgey rear tint (need to find a way to get rid of that).
Family:
2009 Volvo XC90 V8 R Design
- has a louder more obnoxious exhaust than the S8, sounds great! Love this thing - Q7 was double the price, and certainly not double the car!

Sold:
1997 Audi A4
- Hamilton's Club Sport, Achat Grey (will miss the old girl)
Reply With Quote
  #17  
Old 30th April 2017, 09:37 AM
Goran's Avatar
Goran Goran is offline
Senior Member
 
Join Date: Feb 2011
Posts: 1,968
Default

Good info, thanks guys

Next time it goes to zero I won't worry so much.
I wonder how mpg calculations change when we account for all this unused fuel, does that mean our cars actually do better mpg than we think?
Reply With Quote
  #18  
Old 30th April 2017, 10:18 AM
ainarssems ainarssems is offline
Senior Member
 
Join Date: Aug 2010
Location: Rushden, Northants
Posts: 3,038
Default

I think on most petrol cars of this vintage mpg is calculated solely using data from MAF sensor.
__________________

1997 S8 was Cat B write-off in 2007 but still going strong
Reply With Quote
  #19  
Old 30th April 2017, 05:22 PM
Goran's Avatar
Goran Goran is offline
Senior Member
 
Join Date: Feb 2011
Posts: 1,968
Default

I didn't know that, thanks
Damn that probably means its fairly accurate.
Reply With Quote
  #20  
Old 2nd August 2017, 04:12 AM
Ameiseuk's Avatar
Ameiseuk Ameiseuk is offline
Senior Member
 
Join Date: Mar 2016
Location: Newtownabbey, UK
Posts: 353
Default

......Picking up on this debate, the S8 stuttered and spluttered with 40 miles range left yesterday.

Last time this happened was 11pm Christmas night about 3 miles from home and it stopped completely.

At that time I went through the whole fuel pump not seated issue, assumed that at some stage it had been monkeyed with...... but not to be.
Turned out the top had popped off the driver side fuel sender tube and the float seemed to stick/jam near the bottom of the tube.

Anyway duly fixed and reassembled. Ran around for a couple of weeks with 5lt in a can in the boot to see if it was sorted. Ran the car right to 0 miles range, needle firmly in the R zone without a hiccup.

...fast forward to yesterday, thankfully this time I was about 500yds from a petrol station and nursed it to a pump.

Filled to more or less the brim - 88.35lt
Spec sheet states 'Tank capacity 90lt'
Rough calculation 40 miles range @ 20mpg = 2 gallons/9.09lt left
I doubt I'm getting 40 miles on 1.65ish litres of fuel!

Looks like I'm going fuel sender purchasing/hunting
__________________
Daily drive: 2010 Infiniti Fx30D Sport.....a car that's too complicated to modify

Current 'Project': 2000 Audi S8 FL no longer in bits on the garage floor. Solar sunroof, towbar, extended leather, rear+side blinds, Avus alloys and an interior that has now been cleaned

Previous 'Projects': 2006 Subaru Legacy Spec 'B' 3.0R, 1994 Ex-MOD Land Rover Defender, now "civilianised"

www.whall.co.uk
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 04:54 PM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.