Fuel Gauge 1995 Coupe

[evokid]

Just a quick question, ever since ive had the car the fuel gauge has underead!!

When full up it only reads 3/4 Full.... Never seen the low petrol light on as never trust it to go that low....

Are there any ideas on fix for this?

Wondered if dirty contacts OR if Faulty sender/Gauge?

Any one else had this?

[zollaf]

mine is the same. when the guage read empty, i popped the top of the tank and recon theres about 1/4 tank left, so as long as i refuel before it gets stupidly below the red, i will be ok. i have tried twiddling the twiddly knob next to the guage, but that did nowt, so i just live with it.

[scotty33]

I found both of my 20v's had this to a lesser extent. I think the resistance in the circuit increases with age leading to a low reading gauge. Try filling it to the brim from a point when you think it is 'low', the tank holds 70 litres so...
the gauge can be adjusted, the shortest of the 4 'knobs' on the instruments is where the adjustment is. You need to pull out the end of the 'knob' with say a needle nosed pliers. A long series 3mm allen key can then be inserted through the hollow shaft into the potentiometer at the bottom. Adjust needle as required
It is common for the fuel gauge to not read full when the tank is full.
Audi use a set of known resistances at the gauge sender wiring, which should correspond to particular points on the gauge.
I tweaked this setting on my first 20v car, the gauge read almost full when full and the fuel light came on as it should, but I would not do many miles with it on and I was getting 70 litres into the tank sometimes so, my advice is mind how you go if you choose to adjust it....

[andy757]

I filled my 16v 95' Coupe yesterday, £60 to the brim, and the gauge read's 3/4 full !!

Is there a low fuel warning light ? If so, where ????

:confused:

[FSARoyster]

I've got the same issue on my 16v, not tried fiddling with the adjuster yet.

I ran out the day I went to look at the car to buy it, no light, needle just touching the start of the red markings on the gauge, so I currently won't let the needle fall below the 1/4 mark :/

Does the 16v hold 70 litres, or is this just the 20v?

Thanks

Rog

[evokid]

I'm the same, i always refill mine at about 1/4 tank to advoid any nasties!!

But will try the adjustment as supplied by Scotty and report further...

[andy757]

I cant even get the end of the knob off - ooer that sounds a bit porny doesn't it :Blush2:

Is it just the end that comes off or can adjustment be made by turning the knob :confused:

[FSARoyster]

I just went out and used a pair of long nose pliers, just grip the end, although there's not a lot to grip, and gently pull it out. Here's a pic I took so you can see what you'll pull out...

Thanks

Rog

http://i124.photobucket.com/albums/p36/FSARoyster/Fuelgaugeadjuster.jpg

[evokid]

Thanks for pic, i did the same today and adjusted the barrel with 3mm allen key it just seems to move the whole pointer mechanism left or right, so filled mine to fuller than full. And set to full mark on gauge... Will see how we go...;)

[andy757]

I can't even get the friggin knob out to try :buttkick:

By the way, how do I get my profile pic to show on replies ??

[FSARoyster]

Not sure about your profile pic, but someone will no doubt help you on that.

As for the problem with your knob :P (sorry!) As I say get some long nosed pliers grip it firmly and out it pulls, I think once I'd pulled it away slightly with the pliers there's a gap you can then get your finger nails under to pull it out the rest of the way, I was just concerned about ruining the knob. If it doesn't pull straight out, try twisting it slightly both clock and anti-clockwise, as its not likely to have been removed before so needs a little persuasion.

Thinking about it, even if you destroy the knob Audi probably still supply them and it's only a little bit of plastic so shouldn't be expensive, check first at least then it won't matter if you kill it. I would suggest putting a bit of tape of blutac over the hole you leave so as extra dust and crap doesn't get in there until you replace the cap.

By the way this is probably the norm, but my pliers have rough insides, probably to aid with gripping, I guess a pair without the grip will more likely slip off what ever you are trying to grip.

Thanks

Rog

[andy757]

Thanks very much, I will give this a go. Just need to buy the pliers :zx11:

[FSARoyster]

When it comes to tools, although its unlikely to help you immediately, keep an eye on Aldi, they do 'specials' every Thursday and Sunday, and they put the deal info up on their website. A couple of weeks back now I got a set of 6 assorted pliers for £4! If you're lucky, Aldi round my way keep stuff until its sold, so if you pop in your local Aldi on the way home they might still have a set.

http://aldi.co.uk/uk/html/offers/special_buys3_14845.htm

I've had loads of tools from them over the years, power tools are good, tend to come with a 3 year no quible warranty!

I think Lidl do a similar thing, but I don't have one local to me.

Thanks

Rog

[evokid]

Just be aware when adjusting! I filled mine to the brim, adjusted to full scale just below full....But got caught out other day when car started juddering as low on fuel just before even getting to the red line!!! So be cautious if adjust too far....:mad:

[FSARoyster]

I went for the opposite method, my petrol was low, the needle was just before touching the red, it had run out like this a week or two before, no light came on or anything, so I decided I was quite low at this point and adjusted the needle to just slightly above the bottom of the red as it were. I don't plan on letting the needle fall into the red, but at least if it does I should be getting a more accurate reading.

Rog

[andy757]

I adjusted my gauge as suggested, and with a full tank.

It ran dry after 482 miles so I'd say that worked well.

Thanks for the tips and help.

[scotty33]

Does the 16v hold 70 litres, or is this just the 20v?

Thanks

Rog

Most of the bog standard stuff is the same through the years and models, so guess the 16v is also a 70 litre tank, maybe the handbook would confirm?
Stuff like brakes can differ but even then 20v stuff is the same as 2.8 v6, I think your 16v brakes are the same as the 2.6 for example. There are very few changes in the chassis between type 89 coupes and B4 coupes for what it's worth.

[scotty33]

I adjusted my gauge as suggested, and with a full tank.

It ran dry after 482 miles so I'd say that worked well.

Thanks for the tips and help.

482 miles - didn't think they did a diesel coupe!!:beerchug:

[andy757]

It cost me about £67 to fill it up. That was 2 weeks ago and having zero'd the mileometre at that point, it read 482 when I ran out. Not harsh driving, just pottering around the countryside, to-from work etc.

[FSARoyster]

I got just over 400 (408) miles to a tank a few weeks back, didn't let it run out as I've never thought that to be a good thing to do, especially on older cars, as they say you tend to run the risk of drawing through debris from the bottom of the tank.

Mine cost around £70 to fill up, I've been using Tesco's super unleaded (RON 99) stuff.

Thanks

Rog

[raymondbilko]

Hi guys it seems that most of us are having the same problem with the fuel gauge i will try scottys sugestion and see how i go.