Interesting Focus ST thing.

[daveydave]

so this isnt actually improving your fuel economy....just providing you with a more accurate reading?

I cant see the point then, surely you'll still be at the pump on the roughly the sameday you normally were filling her up?

Once you convert that additional 4 mpg to litres, how much is that going to save you on a tank?

 

[mjt]

volvo 5-pots are notoriously uneconomical, so you'd struggle to get decent fuel consumption out of an ST whether you start unplugging things or not

 

[Jonnycoupe]

Its just the long term fuel trims. Adjusting; really they should be applicable to stuff where you not in light throttle cruise where the lambda sensor closed loop would control takes care of stuff anyway.

 

[NVP]

More than likely does, but its finding the correct fuse to pull, maybe that in your car the same fuse is used for other parts of the vehicle.

The other option is to disconnect the car battery for 30 minutes, but DO NOT do this unless you know the security code for your vehicle.

Cheers.

I know that my E46 learns on the fly. I drive it like a grandad most of the time, so when I get in it and the throttle response has sharpened up, it's usually because my missus has just driven it rather enthusiastically.

I may give it a go just to see if I do actually notice a difference...

 

[smokedog]

Even on long trips ~50+ miles it never went above 20mpg.

Ouch, whats the range on a full tank?

 

[Deleted User 234324]

Been getting 190-210 to a tank, should be closer to 250-300

 

[djcj]

Yeah, I average about 270 - 300 miles per tank in mine (and that's running the dsci remap)

 

[matt100]

I remember woohoo on this forum saying he got 30mpg+ on his, I never, ever get over 30mpg on mine.. I know there was a fair amount of "progress" made by me on the last tank and I averaged 23.5mpg

I normally get about 28.. to be honest its rubbish for a reasonably hot hatch..

Still, I don't pay for the petrol so I don't really care, its just inconvenient having to fill up every 270 miles.

 

[thepharcyde]

I always see over 25mpg an I rag it everywhere as it's only a weekend toy.

 

[Simon]

Sounds just like a typical adaptive (not predictive) fuel and idle trim. Take any modernish car with EFI, erase these trim values by pulling a fuse/disconnecting the battery and the car is likely to idle poorly and likely give different MPG until it has re-adapted.

Agreed.

All you have done is wiped the ECU so it has to relearn, it will soon get back to where it was before.

Long term ignition and fuelling trims can be affected by putting in crap fuel in. This effect will stay for a fair few tank fulls

 

[wassap]

I remember woohoo on this forum saying he got 30mpg+ on his, I never, ever get over 30mpg on mine.. I know there was a fair amount of "progress" made by me on the last tank and I averaged 23.5mpg

I normally get about 28.. to be honest its rubbish for a reasonably hot hatch..

Still, I don't pay for the petrol so I don't really care, its just inconvenient having to fill up every 270 miles.

Aye, I used to be able to get 30mpg on a run driving it gently, I even got 36mp on a run up to Scotland. Generally I got 27mpg on the motorway, and 24mpg locally, I drove it reasonably hard on Tesco 95ron, so no special fuel.But as I did loads of miles in it, It got serviced every 4 months or so, which could have helped

Loved mine to bits, still miss it like hell.

 

[monkey_boy]

Perhaps a dumb, but hopefully valid question:

Would this trick 'wipe out' any remap you might have? I've heard of remaps that 'expire' after some time for a trial and wondered if it was related to this Keep Alive Memory thing.

 

[Sin_Chase]

Perhaps a dumb, but hopefully valid question:

Would this trick 'wipe out' any remap you might have? I've heard of remaps that 'expire' after some time for a trial and wondered if it was related to this Keep Alive Memory thing.

This sounds.... unlikely.

Maps are written to a non-volitile memory space (EEPROM for example)it's just a data map that gets read from so I am unsure of how one could upload a map that self detonated and then replaced itself with a base map.

Would be a catastrophe should it try to do it while your car was running!

Either these maps are limited to ECUs which have the ability to do on the fly swaps or other funky stuff (and in my experience these are usually expensive piggyback or standalone units as opposed to OEM) or there are indeed ways of doing this I have never been exposed to or read about.

 

[Overlag]

after a while it will drop back down again. Same happens to my FiestaST.


go for a custom map, the Focus ST overfuels so bad its just wastful.

 

[Jonnycoupe]

This sounds.... unlikely.

Maps are written to a non-volitile memory space (EEPROM for example)it's just a data map that gets read from so I am unsure of how one could upload a map that self detonated and then replaced itself with a base map.

Would be a catastrophe should it try to do it while your car was running!

Either these maps are limited to ECUs which have the ability to do on the fly swaps or other funky stuff (and in my experience these are usually expensive piggyback or standalone units as opposed to OEM) or there are indeed ways of doing this I have never been exposed to or read about.

EEPROM emulator that drops in the 28 pin socket on the ECU. Ive changed maps on the fly for years with a £100 piece of kit. changing a map on the fly, for example a set load site, is what is known in the trade as ..... engine mapping.