Mondeo Mk3 TDCI ECU reset

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Thu 17 Feb 2005 18:37
Mondeo Mk3 TDCI ECU reset - mondeoman
Every time I have my mondeo serviced the MPG increases from 50 to around 54 for the same sort of motoring. I think the car has a ecu which adjusts the engine according to the way you drive, so i would like to know how to reset the ecu myself to save a few bob!! Any ideas?

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Thu 17 Feb 2005 18:57
Mondeo Mk3 TDCI ECU reset - mfarrow
Interesting finding. How do you know the ECU is reset when you have it serviced? The ECU can only be reset by disconnecting battery I would have thought.

How long (time/miles) does the increased MPG last? My reckoning is that the engine's just running more smoothly thanks to newer oil.
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Thu 17 Feb 2005 18:58
Mondeo Mk3 TDCI ECU reset - Dynamic Dave

More than likely it's a new air filter that could be making the mpg difference.
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Thu 17 Feb 2005 19:54
Mondeo Mk3 TDCI ECU reset - mondeoman
Improvement lasts for 2-3 hundred miles, last time I had it serviced I drove to cardiff from norwich and averaged almost 60 mpg there, on the return at slightly higher speeds the average overall dropped to 50 overall
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Thu 17 Feb 2005 19:59
Mondeo Mk3 TDCI ECU reset - Bill Payer
Perhaps the new engine oil is slippier at first, but then it's quickly losing its intitial slippieness?
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Thu 17 Feb 2005 23:59
Mondeo Mk3 TDCI ECU reset - Dynamic Dave
I drove to cardiff from norwich and averaged almost 60 mpg there, on
the return at slightly higher speeds the average overall dropped to 50 overall


As you made the return journey at a slightly higher speed, it's more than likely this is the reason why the mpg was less than the initial journey there.

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