Technical Fuel Consumption of Uno???!!!

[CyberMunky]

I have been using my Uno 1100 Fire for a couple of weeks now and am getting quite worried about its fuel consumption. After filling up with 33 Litres of fuel i am getting between 350Km (Heavy Foot) and 370Km (Eco Foot) till the light comes on. Now this works out to be about 9 litres per 100Km's! My dads 2.0L Spoptage does close to that!

Please could someone tell me what the counsumption should be like and what could be causing the excessive fuel usage.

 

[Peterg]

I manage 350 miles per tank in my 1108cc fire so you are certainly using a lot of fuel somehow.
Pete

 

[A_Acolyte]

I manage 350 miles per tank in my 1108cc fire so you are certainly using a lot of fuel somehow.
Pete

Thats 560 kms.

Well, since widening my carbs main-jet, I'm getting pretty crappy economy too. I have a hunch my air-filter is partly to blame, however....

Perhaps you could look there - maybe its clogged?
-Acolyte.

 

[(CZ)enda]

Typical fuel consumption of 1.1 Fire should be 5.5 - 7 l/100 km in mixed traffic. However, if you drive in city traffic only, I would thing that even 9 l can be realistic .
It is hard to guess what causes the high consumption... possibilities are almost countless (underinflated tires, air filter clogged, thermostat sticking open, spark plugs worn/with wrong gap, ignition timing misadjusted etc. etc.).
Is it carburettor or SPI model?

 

[CyberMunky]

Im getting 9 litrs on combined cylcle, both city and highway. I know its not the tyres (I often reinflate them). The disposable air filter was cleaned in its last service......thats not supposed to happen is it?

Weber Carburettor.

 

[CyberMunky]

I just had a peek at the air box and the thermostat (i think its called) that opens the flap for the cold air. Now is it meant to be closed? It was only partly open. I know hardly anything bout cars so I dont know.

 

[(CZ)enda]

None of the things you mentioned should increase consumption dramatically.
Air filter should be replaced, not cleaned - it is not worth the effort anyway, it is not that expensive.
Flap has some limited effect on consumption, but I do not think it would be that drastic.
My suggestion is to check spark plugs first. If they are black, the mixture is too rich and consumption therefore too high. If they are brick-red, mixture is OK. If grey, it is too weak.
This will also be useful for checking general status of the plugs. If in doubt, I would suggest changing them for new ones, again, standard plugs are not all that expensive.

 

[A_Acolyte]

I noticed a performance drop in my car around about the same time that it started using oil. Not much oil (maybe one can per 2-3 tanks?). I still haven't worked out where the performance went - we've checked (and rechecked) mixture and timing.

Fuel consumption also increased around the same time. It may not be related, but maybe it is?

Perhaps Cybermunkey and I have a similar problem?

When you guys speak of 'gaps', what are you referring to? How can I check my 'gaps'?

Thanks for any input.
-Acolyte

 

[thepottleflump]

Gaps may refer to the spark plug electrode gap and is measured with a feeler gauge.

 

[Peterg]

Ah if you are loosing oil then the reason behind that could be your problem.
Pete

 

[CyberMunky]

Im not losing oil!

But about the spark plugs, how do i remove them to check?

 

[Peterg]

Sorry got mixed up with another members posting on this thead.
Pete

 

[(CZ)enda]

But about the spark plugs, how do i remove them to check?

Get a socket wrench for the spark plugs at the nearest gas station (cheap Chinese wrenches are less than 2 Euro where I live), then use Haynes manual for pictorial guide .
Sorry, I do not dare to explain this when 1 picture tells more than 100 words. And, as you say that you have zero experience with cars, it seems advisable to study the theory first.
"Gap", indeed, refers to the gap between the electrodes of the spark plug. It should be 0.6 - 0.8 mm (references vary).
I never had to adjust the gap, all new plugs I ever bought came with the gap set to this value by their manufacturer :idea:

 

[Louie Bee]

LB's Fuel Consumption

...Please could someone tell me what the counsumption should be like and what could be causing the excessive fuel usage.

Hi All,

I have managed around 50.5 MPG (422 Miles on 1 Full tank [38 L - 8.36 Gal]) on a long run of mixed driving from my 1.0 IE.

I spent a lot of time slipstreaming lorries until a Mc Donald’s lorry had a pop at ramming me off the road near the M6 Knutsford junction .

Within the journey, I did some off roading too which will have taken the MPG down a tad .

Regards All,
Louie Bee.

 

[alexGS]

Re: LB's Fuel Consumption

I spent a lot of time slipstreaming lorries until a Mc Donald’s lorry had a pop at ramming me off the road near the M6 Knutsford junction .

Within the journey, I did some off roading too which will have taken the MPG down a tad .

Louie...
I was really laughing out loud...
We have discussed your aggressive driving before, y'know
I even know where the Knutsford M6 junction is.
And... I like that reference to 'off roading' within the journey! as though that would be a natural consequence of the driving...

Anyway for those of us that stay on the road, I think 7.5L/100km (37mpg) would be a reasonable value to expect for average around-town driving. I used to get that with my old Uno 60 (1116cc). 999cc FIRE should be a little more economical - perhaps up to 6.5L/100km (44mpg).

Cybermunky:
If economy is worse than this, check the engine timing (including vacuum advance) and the spark plugs (as already pointed out). But also, try pushing the car by hand on a flat surface. It should be quite easy to roll (brakes not binding, tyres inflated to 30psi - although 27.5psi is the recommended pressure).

Make sure your economy measurement is accurate by filling the tank consistently to the second 'click' of the fuel pump's auto shutoff, and perhaps even verify that the odometer is correct over a known distance.

Ensure that the engine is warming up properly within a few kilometres (temperature gauge reading 80-90, about halfway). Thermostat stuck open is a common fault. Also inspect choke mechanism to ensure choke is 'off', and ideally check carburettor float level to ensure that there is no flooding. Is the engine easy to start?

With petrol prices the way they are - I hope you find an answer...

-Alex

 

[SteveNZ]

wow, Uno60s gets good economy! My mk2 turbo gets 10L/100k with my mods if I drive it very sedate. My Mk1 was heaps better 7-8L/100k if you drive it nice.

It cost me $72 to fill the tank the other day and it was not totally empty! It cost more than my Tipo!

 

[Chas Uno]

I just had a peek at the air box and the thermostat (i think its called) that opens the flap for the cold air. Now is it meant to be closed? It was only partly open. I know hardly anything bout cars so I dont know.

When the engine is cold, the cold air flap in the air filter should be completely shut. Only when plenty of warm air comes into the airfilter housing should the thermostatic actuator open the cold air flap.

Also, the air filter for the standard air filter housing is the disposible type. If it's been 'cleaned' (not supposed to do that), it's possible that it has become clogged up instead which would explain the poor fuel consumption. A clogged air filter will restrict air flow and cause the carburetor to run rich, hence increasing fuel consumption. An air filter costs very little and is a doddle to change (about 30 seconds max!) I'd do this first before anything else.

As for consumption, I once got 400 miles to a full tank on my Uno FIRE. Did some calculations and it turned out to be doing around 60mpg! Normally I get around 40 - 45mpg round town, and well into the 50's on a run. At current UK prices, £10 is equalling 100 - 110 miles if anyone has access to an MPG calculator

Chas

 

[(CZ)enda]

My carbed 45 (200k km on the odometer) recently made 6.18 l with 4 people and baggage inside, 110 - 130 km/h on freeway, fighting with strong wind blowing in opposite direction all the way.
Then 5.35 with 2 people, speed about 90 km/h.
This (expected from the one I had before) consumption is result of:
-complete front/rear brakes renovation (they were sticking)
-new thermostat (engine temperature hardly ever reached above 70°C)
-new spark plugs (just for the feeling, they were not that bad)
-new air filter (same as above)
-new summer 135 tires (selected carefully to provide minimum drag/maximum safety) instead of winter 155.

The combination of these actions improved the consumption by about 1l/100 km.

 

[M@nticore]

Well I get roundabout 12 - 13 km per litre when i'm drivingthe **** out of the car, normal driving 15 -16 km per litre.
When my car was my moms she managed 20 km per litre, and i've seen it for myself as I didn't beleive it. She had a .95 main jet in and was driving slower than my grandma .

 

[CyberMunky]

Re: LB's Fuel Consumption

Ensure that the engine is warming up properly within a few kilometres (temperature gauge reading 80-90, about halfway). Thermostat stuck open is a common fault. Also inspect choke mechanism to ensure choke is 'off', and ideally check carburettor float level to ensure that there is no flooding. Is the engine easy to start?

Shot for your help man. About the temperature, it takes ages for my car warm up to the halfway mark! Is that bad and what could be the problem?