Fosters

I just went to the SIDC page to look up ECU resets and what they do for you - it's down at the mo' so...

This was sparked off by the mpg thread currently running.

What advantages are there in reseting the ecu and under what circumstances might you do it?

I've got a MY00 ppp and always run on SUL - do I need to reset the ecu due the fact that I always run on SUL but the car was expecting NUL when I took delivery?

chuckster

Quick answer - no. The ECU will detect (by lack of knock) that you are running a better quality fuel and will adjust settings untill as optimal as possible given your current configuration. The leaflet you get with a PPP states that the car will run better, smoother, more powerfully, on SUL. The car is mapped for 98 or 97, when running on 95 it compensates by retarding the timing/boost, ie it was never 'expecting' NUL.
Cheers
Chuck

BarryK

From a non technical layman:-

I think the general gist of recent previous postings about this was if the car has always run on SUL then resetting the ECU is a waste of time as it will never have retarded the ignition anyway, ie there is nothing to fix.

As far as I am aware from various stuff I have read here, the later ECUs (MY99 on?) are better at learning than the earlier ones, so they adjust to how you drive,type of fuel etc. BUT ONLY UP TO A POINT. You cannot transform the engine's performance by putting aero engine fuel in it for example. The ECU will just waste it, oh and it'd probably blow up in fairly short order!

You can replace the ECU with a different one, which should be remapped to your particular engine spec, but that naturally invalidates the warranty, unless like you Prodrive have done it. Similarly a piggy back chip will achieve "improved" results, but from general commentary on here is more risky, because it is too "general".

So, if the car has been run on poor NUL, then the change to SUL would be recognised more quickly if the ECU was reset, otherwise, no point as over time the ECU will stick its snout out until it gets bitten again or is happy.

Do a search by User "Otis" and read his and others comments regarding the reset.