Detuning 2.0 16V

[dnsey]

Whilst the 16v 2.0 Xantia returns respectable fuel consumption on longer journeys, my wife is finding it thirsty for her relatively short trips.
I know that there are specialists offering tweaks to the ECU software to improve performance, but does anyone kow of any modifications (software or hardware) to improve fuel consumption at the expense of performance?

Thanks in advance for any replies - the site is running fine tonight, but I'll probably have to wait a few days until it's good again to read follow-ups

[Mandrake]

What about a brick under the accelerator pedal ?

Seriously.

The only thing you could do to ECU programing to improve fuel economy would be to limit the maximum fueling - otherwise known as not pressing the accelerator all the way to the floor

Regards,
Simon

[Stempy]

I remember in the motorbike world they used to restrict bikes by fitting a disc with a hole in it somewhere along the intake tract so as to limit the maximum amount of airflow, might be worth a try.

[CitroJim]

Simon is quite right

Generally, the turning for performance (within limits obviously) is precisely the same as tuning for economy; the two go hand-in-hand. The goal in both instances being to make the engine run as efficiently as possible for a given amount of fuel. So, if you have a well tuned engine and use it gently it'll be economical. It just takes restraint and cultivating a feather foot on the accelerator and learning the techniques of driving for economy.

Unfortunately, there is no magic ECU tweak that will improve economy drastically.

In the final analysis, good maintenance of the engine and drive-train, ensuring the brakes are not binding, tyre pressures, tracking and not carrying excess weight around make a far bigger difference to economy than any ECU tweaking might.

Try Shell V Power petrol or similar. More expensive I know but the higher octane allows the engine to run with more ignition advance before the knock sensor activates and thus more efficiently. It makes a noticable difference in my Activa.

[jeremy]

I expect the throttle cable is the same as that fitted to the diesels - with some rings cut in the plastic outer sleeve at the engine end with adjustment made by a spring clip fitting in a groove.

If so you can prevent the throttle opening fully by moving the clip to another (slacker) position. Do this enough and the throttle won't open fully.

Generally the best economy is achieved with a properly tuned engine (ie developing full power) which is driven gently. The mixture will richen on acceleration from say 15:1 to 12:1 - so a low powered engine driven with a wide open throttle to achieve a satisfactory cruising speed will be tending to run at 12:1 rather than 15:1 as the more powerful engine gets into its stride.

[Bootser]

Try Shell V Power petrol or similar. More expensive I know but the higher octane allows the engine to run with more ignition advance before the knock sensor activates and thus more efficiently. It makes a noticable difference in my Activa.

I agree , i use V Power in my activa , it does make a difference .

[oscarloco]

Try Shell V Power petrol or similar. More expensive I know but the higher octane allows the engine to run with more ignition advance before the knock sensor activates and thus more efficiently. It makes a noticable difference in my Activa.

I agree , i use V Power in my activa , it does make a difference .

On my ZX, V Power actually rised the fuel consumption. But then again, ECU is an Magnetti Marelli 8P.

[NiSk]

Try taking the lead weights out of the wife's driving shoes . . .

//NiSk