Just measured my town running fuel consumption of Optimax today and it's 17 MPG!

I am not heavy footed and rarely bring the turbo in in the town. Could there be a problem somewhere? It appears to drive fine enough although on light acceleration there seems to be very slight surging, as if the turbo spools up and then stops, spoools up again etc etc.

Maybe I'm wrong but I would have expected around 25 MPG the way it's driven.

Help chaps please this'll kill my wallet if it goes on much longer!!

 

Yeah feckin right.

I reckon I'm well under 20mgp. (MY00 classic, with decat no other mods)

I once got about 30mpg on the motorway

 

If your worried about fuel dont buy a 4wd turbo sportscar...:-)

I never think twice about my fuel because i realised the implications when i bought my beast and love every min i am in it.

Its normal mpg your getting...maybe think about buying a day to day diesel car and have the scooby as the second car, my sccoby is the second car..so maybe dont hit me wallet as much as yours..

 

I wish I got 17 MPG

Just this week I got 95miles to a full tank

 

I do know what I bought and I did expect heavier fuel consumption than I was used to, but I don't drive the car hard in town and two of my friends have exactly the same car and get far better consumption than I do so there IS something not right. I can do without the 'buy a diesel if you want good fuel consumption' comments, you are missing the point. Thank you.

 

What model do you have m8?

 

I have a MYoo and to be honest that all i can get in the town


Buy a diesel whoops sorry someone said that one

 

I don't think he woz taking the ****, it seemed quite a serious comment.

Personally my car almost never sees a motorway, and that's the sort of mileage I get, whether I've been hoofing it or not, on a full tank (about 40 odd quids worth) I expect to get 220-230 miles, it never changes whether the weathers bin bad or not.

If you really do believe your vehicle is at fault other people may be able to suggest something. When you say a "slight surging", exactly what do you mean? That the power suddenly comes in and then drops off again, or just that the power suddenly comes in?

 

It's a 00MY no engine mods yet other than an ITG filter.
It's almost as if you are playing with the throtle...on and off on and off...... very slight but it's there.
My mate has a 98MY with 285 BHP and gets 24-26 in town. My one is standard so should get at least the same. I am hoping that the de-cat next week helps.

 

Could be the lambda sensor is getting ready to die, or the coolant temp sensor is acting up. Both of these will cause rich running and possible hesitation.

Are the exhaust pipes sooted up?

PS My rattly old MY96 gets 23 to 25 mpg in town

[Edited by dnb - 12/14/2003 9:49:49 PM]

 

decat will make you smile and your reear passengers deaf !!

never noticed better consumption with mine as you boot it even more to hear the noise

 

25 mpg i couldnt even get that when my car was standard 17 mpg is close enough to what i get, i would say £20 worth of optimax gets about 50-60 miles around the streets if your lucky

 

I wish I got 17 MPG in town
average on my00 is 220 on a full tank

 

If you're getting less than 25mpg on a long & gentle journey, your lambda's knackered. 20mpg is not normal or expected for typical driving! Lambda sensors should be replaced every 30k or 3 years - they are a consumable. As they age, they under-read, causing the ECU to overfuel on cruise - bad for economy, the pocket & the bores, over time!
If your 'on boost' performance is fine, it's quite possible your lambda's knackered. I'd get it sorted if I were you If your 'on boost' performance has gone a bit odd, look for leaks & stuff

 

Also bear in mind that Scoob's do run rich from standard and thus guzzle more, if your mate has had ECU work done then it is likely to be more economical.

I agree with DNB on the Lambda as this measures the mixture as it comes out of the engine. As these fail your engine then tends to run rich. It's my understanding that they start to go after about 30k.

 

Thanks for the tip guys, I'll change the lambda and see if that makes a difference.
Any idea how much they are and how easy to change. I would assume it's just a swop out and no re-setting of anything needed?

[Edited by Derek FKS 85 - 12/15/2003 7:42:28 AM]

 

Motor Factors in Edinburgh You don't need to, but if you reset the ECU, it would also give you the opportunity to see if your MAF's OK.

 

How easy is it to re-set the ECU?

 

Piece of cake mate! Click here and follow the instructions...

 

Mmmmmmm..... a bit dodgy for me to do that Judge but thanks anyway mate!

 

I also have an my00, and found that the best i've ever managed is 240 miles to a tank, but it's generally less.

I'm led to believe that the 802 ecu, over fuels quite considerably. Good for knock, bad for economy! Also I experienced the hesitation on acceleration, mainly in higher gears. Is this the same as you?

I changed to a Tek 2 ecu on Saturday, and this seems to have stopped the hesitation. So i think it was a trait of the standard map.

Hope this helps

 

Why dodgy?! It's dead easy, honest...

As for the hesitation and over-fuelling, you're right, they are known AE802 characteristics. A manual boost controller can help. It's a hell of a lot cheaper than a re-map, although admittedly not as safe. It helps my taking advantage of the slightly richer fuelling, and also bypasses the boost solenoid, which can be one of the things that causes hesitation (mine did anyway!). Just be cautious, as you're taking control away from the ECU. A few gauges are awlays a good idea...

 

I had this with my old MY 00 and changed the AE802 ECU for an older (but better) AE801 ECU. Not sure if the fuel economy got better, but the hesitation disappeared. Is the hesitation around the 3 to 4 k rpm range ? I would go along to your local meet and ask someone with a MY 99 if you can try there ECU for 30 mins or so

If your near to Bristol, you welcome to try mine

I've since got rid of the MY 00 and bought a MY 99. I had a Tek 2.5 (John Banks) fitted and can honestly say car is returning 32 MPG on a run with air con on So I get better performance and as a result fuel economy is increased over the stock MY 99 ECU and MY 99 PPP ECU If you keep the car for a few years, the remap is the way forward. A AE801 will set you back £150 second hand. A Tek 1 flashed onto your AE802 will make a hell of a difference

Hope this helps, Phill

 

Thanks guys.
I went to my local dealer at lunchtime and he basically confirmed that the hesitation is a trait of the car, which I am quite happy with. I also bought a lambda sensor which I'll fit tonight. He also said that this was the most likely cause of poor consumtion.

Hope I havn't wasted my £104!!!!!!!!

[Edited by Derek FKS 85 - 12/15/2003 2:05:20 PM]

 

422 miles to a tank?!?!?!? You sure that's right? You'd better not let Gordon Brown here about it. He'd probably impose excise duty on Tek remaps...!

 

As I said 32 MPG consistantly, but I have to take it quite easy and cruise around 80 to 90 MPH

I never run the tank empty, as I don't like doing that, but will see 320 to 340 on 7/8 of a tanks In fairness though around a track I can get that as low as 7 MPG

Phill

 

I suppose if my willpower was good enough to drive around without invoking the turbo, I could probably get more out of a tank... but it isn't, so I'll have to make do with 220 ish out of 50 litres.

 

PS MY 99 / 00 have 60 litre tanks

Phill

 

Indeed, but I never let mine run below 10 litres, so my calcs are based on 50 litres...

 

Thankfully the 03's are more efficient! I get 30mpg easily on a long run, even when averaging 50mph on winding roads in Scotland.
Sorry, I know this isn't helping your case, but it's useful info.