Fuel Gauge Operation?

[dave hendy]

I have now had my iQ2 for 2 weeks and I can't work my fuel gauge out! When I bought the car from Jemca Toyota it was showing 3 quarters of a tank, I do 15 miles a day and after 2 days it had dropped 2 bars (worryingly). I filled it up last weekend and have done 75 miles this week and it hasn't dropped off full which doesn't seem right for a 32 litre tank??

What sort of mileage figures does your iQ's drop down a bar from full? Is my gauge faulty? My trip computer was showing 52 mpg although I worked it out at about 48mpg which I was a bit disappointed with as I have been driving like Miss Daisy as the car still hasn't done 200 miles!

Anyway gave it a treat yesterday and spent 4 hrs washing and polishing it

[en8wall]

I've done 100 miles before the first bat has gone. The other bars do tend to drop quicker....must be the shape of the fuel tank I guess.

[Gordon in Angus]

I found that if I filled the tank to the brim and averaged 53pmg I'd get about approx. 110 miles on the car by the time the first mark clears and approx. 64 miles between each other mark. There's almost another 3 litres in the filler neck and the tank if you carefully fill it up to the brim hence the bigger first mark or 6th of a tank. That all does depend on your average mpg though, which was down on my car for the first 1000 odd miles. That was all largely consistent once the first couple of thousand miles were passed and the car was run in a bit.

That any help?

Gordon

[IQ Old git]

My Iq3 tends to do about 100 on the first mark (I fill right to the brim each time) then each bar goes quicker and quicker. Usually it does about 300 when the last one starts flashing. I have signed up to 'fuelly' (free) (how do they do that) and was pleasantly suprised that my first result was 55.8 with my gauge reading 53.6 just before it started flashing. Im now only using the gauge as an approximate indication as it varies widely for the first 150 miles with the slightlest of hills making it plumet. Still not worked out how to disable the stupid reset each time you fill up. If it could be left to do a lifelong reading with reset on the button you would get a stable and probably more accurate reading. My old Yaris T sport (Mk1) 47.7 was within .3mpg over 27,000 miles. Yes I did the envelope/pencil record as well (mainly for business reasons) Best of luck with your 'new' car. Like mine I expect it will get used to you. (Still missing the Yaris ease of drivability) It would go any and everywhere in top gear. Bliss. Cheers Colin

[FROSTYBALLS]

The fuel gauge is similar to some other models such as the Auris, Yaris, etc. It doesn't operate in a linear fashion and the bars of the gauge go out faster the more the tank nears empty.

A good example of this is the following topic - http://www.toyotaownersclub.com/forums/topic/157794-auris-133-fuel-bar-fuel-consumption-and-all-that-stuff/

It is something you will get used to.

[ToyotaAuris]

If its like the Auris like Frosty said then dont worry. Its always like that lol.

[dave hendy]

Thanks for the replies, that puts my mind at rest I thought it must be faulty staying on full so long! Must be differcult getting the gauge unit to work properly with the thin tank. I just need to get used to the cars ways!

[IQ Old git]

Just an update. My first segment went out at 134 miles after brimming tank. Hope this helps.

[dave hendy]

Just an update. My first segment went out at 134 miles after brimming tank. Hope this helps.

That's incridible, thanks for the info!

[IQ Old git]

Bad news, the gauge started flashing at 275mls, on ordinary u/l as opposed to 300/305 on super. Mmm that'll knock my fuelly reading down. Off to fill up again.

[en8wall]

Slightly off topic and maybe a stupid question....is it ok to use super unleaded and will it actually improve mpg?

[dave hendy]

Yes and possibly although not tried it myself!

[Andy Kay]

Slightly off topic and maybe a stupid question....is it ok to use super unleaded and will it actually improve mpg?

From what I read it is certainly okay, and it may improve mpg but any improvement may be completely neutralised by the extra cost. It contains cleaners that keep the engine flushed, so may improve performance and engine life. I understand the greatest gains are to be had by the highest performance engines, so I guess that excludes the iQ.

[IQ Old git]

So here is my experience so far. My first fuelly reading on 'super' gave 55.8mpg the second on ordinary u/l 52.0 with average of 53.9. I have now refilled with super which was + £2.60 (@ + 10p) and an approximate calculation shows it to be very slightly more expensive using super, my useage has been the same (obviously this needs to be done over a big mileage to prove anything) but I thought it worth the extra which will hopefully negate the use of injector cleaner every few thou miles. My experience on my previous Yaris T sport was that it made no difference whatsoever, it did 47.7 mpg whatever you put in it. Tried over six tankfulls of super, which I gave up on as it was approx £4 a tank extra. Strange as it was a 'high performance' engine. Clearly I was getting the most possible out of the Yaris. (I have been accused of driving like a granny) One friend even suggested I should swap it for a 2CV. Thanks Chris. Cheers. Colin, hope this helps.

[Grumpy Cabbie]

Slightly off topic and maybe a stupid question....is it ok to use super unleaded and will it actually improve mpg?

Some say the benefit of Super 98/99 unleaded is all in the mind. Some argue you will get less mpg's using it. But I think it all depends on the car, the actual use of the car and how old it is.

I think if you use your car on a run daily such as a nice commute or motorway work, then any petrol is fine. If you use the car for mainly town or short runs then I've found Super works in that the car runs sweeter. Again some will argue this is not the case or it's all in my mind but the one proof I have is this;

Mrs Cabbie notices the difference that VPower makes to her 1.0 2010 IQ Auto which is used for short runs in town about 30 miles daily. She swears by it now. If Mrs Cabbie notices ANYTHING about how a car runs, then the difference/change is obvious.

Perhaps it's evidence many won't accept, but if you knew her and her knowledge of cars, then you'd accept it.

To be fair though, I'm not sure there is any mpg benefit or if there is it's so small as to be negligible. To us it's the smoothness, the smooth acceleration and cold running benefits that sell it.

[TopIq]

I tried using Tesco 99ron for 3 months in my 1.0 manual but just couldn't feel the difference (sorry). I usually do a 3ish miles a day driving to work and back but I recently did a 500 mile trip (over 3 days) on mainly motorways. The following morning when I drove to work the difference in power was astonishing and it felt so much more responsive.