fuel gauge behaviour

Author
Discussion

cre8toruk

Original Poster:

250 posts

142 months

Thursday 7th February 2013
quotequote all
Hi

Upon starting my 111s, i note the the fuel gauge light is showing.. after about 5 mins the light goes off and i seem to have more fuel showing on the gauge...thoughts anyone ?

schrodinger

201 posts

195 months

Thursday 7th February 2013
quotequote all
cre8toruk said:
Hi

Upon starting my 111s, i note the the fuel gauge light is showing.. after about 5 mins the light goes off and i seem to have more fuel showing on the gauge...thoughts anyone ?
Admiral Akabar said:
It's a trap!
wink

seriously - think of the fuel gague as more of an indicator of the rough amount of fuel that might, possibly, be hiding in the tank. And use your trip meter as a more accurate indicator.


Thorburn

2,406 posts

198 months

Thursday 7th February 2013
quotequote all
The real fun comes when you discover you have 10l in your tank still, but that because you've parked on a slope the fuel pump can't pull any of it through. wink

Also the moment it says REFILL, panic. You might have 10l left, you might have nothing. I've filled up within a mile of it coming up once and put in 40l.

cre8toruk

Original Poster:

250 posts

142 months

Thursday 7th February 2013
quotequote all
Heh yeah.... filled up took 28 litres... which means i had 4 left... only did 135 miles do mpg wasnt great...

Platinum

2,101 posts

228 months

Thursday 7th February 2013
quotequote all
I tend to fill up when it's showing 2 bars remaining - just to be on the safe side!

Thorburn

2,406 posts

198 months

Friday 8th February 2013
quotequote all
cre8toruk said:
Heh yeah.... filled up took 28 litres... which means i had 4 left... only did 135 miles do mpg wasnt great...
Should have had more than 4 left, it's a 37l tank + the filler pipe isn't it?

subaqua

892 posts

217 months

Friday 8th February 2013
quotequote all
The real fun come when you have swirl pots additional fuel pumps and your car shows 11 litres but you have just run totally dry. On this set up the fuel pressure remains unchanged until basically the last drop. No coughing, No spluutering, 50 yards and then its dead, on the M25.

It was very lucky I was on the slip road not the o/s lane.

Never..... ever..... trust a lotus fuel gauge. Count the miles.

Exige77

6,522 posts

196 months

Friday 8th February 2013
quotequote all
^^^^^^ What he said.

We often do Euro trips with large groups.

We fill up together to stay in sync but the fuel gauges are all over the place.

Much radio banter: I've got 2 bars left, I am still half full, mine says empty but wait a minute now it says 2 bars WTF.

Never trust a Lotus fuel gauge.

I can't imagin how the V6 supercharged Exige will fair with just 40 litre tank. It will be reading half full then 10 mins later you will be at the side of the road waiting for the AA.

Ex77

kambites

68,179 posts

226 months

Friday 8th February 2013
quotequote all
Thorburn said:
cre8toruk said:
Heh yeah.... filled up took 28 litres... which means i had 4 left... only did 135 miles do mpg wasnt great...
Should have had more than 4 left, it's a 37l tank + the filler pipe isn't it?
I've seen various numbers. The brochure states 32 but I've got 34 into mine before. 36 seems to be a common figure.

In answer to the OP, the gauge is rubbish. I can park my car across a slight slope when it's half full and it'll read empty when I start it up again. Parked on the flat it seems pretty consistent, though.

cre8toruk

Original Poster:

250 posts

142 months

Friday 8th February 2013
quotequote all
Thorburn said:
Should have had more than 4 left, it's a 37l tank + the filler pipe isn't it?
32 according to the manual

cre8toruk

Original Poster:

250 posts

142 months

Friday 8th February 2013
quotequote all
Exige77 said:
^^^^^^ What he said.

We often do Euro trips with large groups.

We fill up together to stay in sync but the fuel gauges are all over the place.

Much radio banter: I've got 2 bars left, I am still half full, mine says empty but wait a minute now it says 2 bars WTF.

Never trust a Lotus fuel gauge.

I can't imagin how the V6 supercharged Exige will fair with just 40 litre tank. It will be reading half full then 10 mins later you will be at the side of the road waiting for the AA.

Ex77
Well that's all very well but how do I know how many miles it should have done ? My 2nd fill up ever and it did 135 miles... which if I put in before what I put in now would equate to 23mpg or Rubbish as I like to call it.... :-) So how many miles should I expect, full tank to full tank ?

kambites

68,179 posts

226 months

Saturday 9th February 2013
quotequote all
cre8toruk said:
Well that's all very well but how do I know how many miles it should have done ? My 2nd fill up ever and it did 135 miles... which if I put in before what I put in now would equate to 23mpg or Rubbish as I like to call it.... :-) So how many miles should I expect, full tank to full tank ?
I've never managed to get under 200 miles from a tank in mine on the road, even on my commute (which is only four miles so mostly run cold). On a long, fast cross-country run I get closer to 300 miles. On the motorway 350 is possible if you REALLY try.

If you're getting under 30mpg there's probably something wrong.

CocoUK

991 posts

187 months

Saturday 9th February 2013
quotequote all
The Lotus fuel gauge, a fun game all in itself.

As mine is a weekend warrior I just throw juice in whenever I take it out or if the empty indicator is being very persistent/persuasive/annoying/convincing (delete as applicable). Having said that, I have found new homes for far too many fuel-cans...

cre8toruk

Original Poster:

250 posts

142 months

Saturday 9th February 2013
quotequote all
kambites said:
I've never managed to get under 200 miles from a tank in mine on the road, even on my commute (which is only four miles so mostly run cold). On a long, fast cross-country run I get closer to 300 miles. On the motorway 350 is possible if you REALLY try.

If you're getting under 30mpg there's probably something wrong.
Well that is the worry yes.... one of the attractions was the fuel economy (and a lot other things too mind you)... Will monitor and get it looked at if it's not right next time.

I'll aim for 200 miles and see...

8.

jfk01

106 posts

189 months

Sunday 10th February 2013
quotequote all
40mpg is well realistic for a 900 KG car with a modern powerplant ...
52 mpg has been reported from one trusted owner

kambites

68,179 posts

226 months

Sunday 10th February 2013
quotequote all
jfk01 said:
40mpg is well realistic for a 900 KG car with a modern powerplant ...
52 mpg has been reported from one trusted owner
I've seen 50 slip-streaming lorries on the motorway. Anyone claiming to average 52 is either lying or has bought the wrong car. smile

schrodinger

201 posts

195 months

Sunday 10th February 2013
quotequote all
I think this is a bit pessimistic.

Seloc wiki says tank capacity official = 36 l, but a completely empty car could be up to 45l to fill.

I've certainly done 20-30 miles with _no_ bars showing on the gauge... and then put 40l in it. (and also breathed a big sigh of relief)

chris7676

2,685 posts

225 months

Monday 11th February 2013
quotequote all
schrodinger said:
I think this is a bit pessimistic.

Seloc wiki says tank capacity official = 36 l, but a completely empty car could be up to 45l to fill.

I've certainly done 20-30 miles with _no_ bars showing on the gauge... and then put 40l in it. (and also breathed a big sigh of relief)
I put 42 l after running out(!)
Never trust the official data or the gauge.

Btw, my 1999 111S did around 34 mpg of mixed driving.
20-22mpg was only achievable on the track smile

Thorburn

2,406 posts

198 months

Monday 11th February 2013
quotequote all
kambites said:
I've seen 50 slip-streaming lorries on the motorway. Anyone claiming to average 52 is either lying or has bought the wrong car. smile
I'd guess that was a 1.6l car on a long motorway run.

When I had one for the day I got just over 40mpg out of it in a mixture of around town driving, motorway and country lane thrashing of it. Had bang on 40mpg out of my S1 on a very boring drive to Scotland, so the 1.6 is definitely more economical than that.

schrodinger

201 posts

195 months

Monday 11th February 2013
quotequote all
chris7676 said:
schrodinger said:
I think this is a bit pessimistic.

Seloc wiki says tank capacity official = 36 l, but a completely empty car could be up to 45l to fill.

I've certainly done 20-30 miles with _no_ bars showing on the gauge... and then put 40l in it. (and also breathed a big sigh of relief)
I put 42 l after running out(!)
Never trust the official data or the gauge.

Btw, my 1999 111S did around 34 mpg of mixed driving.
20-22mpg was only achievable on the track smile
See? perfect. I had a whole 2 litres left. Could have done another 15 miles!