Technical seicento mpi ecu reset bad mpg

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Technical seicento mpi ecu reset bad mpg


May 1, 2010
seicento ecu reset due to bad mpg ? my sei has had quite bad mpg and bit of a lumpy idle any help would be appreciated :confused:

had a full service last week plugs ht leads oil and filter
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with the cheapo reader i have all seams ok and a friend of mine from hear reset codes with hit top of range machine.
Lumpy idle is most likely down so something else. Indeed, re-setting the ECU will generally cause the car to run a bit off till it relearns.
I got told by fiat themselves to rest the ecu you have to get it very hot and rev it to 5 k and release 3 times
im on about hard reset not codes unless there the same thing tried the battery disconnect all night method taking for good run tomorrow se if anything happens
Disconnecting the battery will clear fault codes but as seicento sam has pointed out to reset the ECU rev the car to 5k (some say 6k) let it come back to tick-over then do it twice more.
The ECU relearn takes quite some time so you really need to drive it for a long period at all speeds/engine loads- not thrashing the be-jasus out of it & expecting it to be perfect.
Chances are an air leak is causing the lumpy idle/bad MPG so resetting the ECU won't fix the problem, but you've already been told this.
MES (formerly Fiat Ecu Scan) or a code reader that will capture live data should do it.

Alternatively, you can attack individual sensors or components with a multimeter.

My guess is it'll be ignition related, so the run the car in the dark, ait filter gubbins off. look for blue flashes trick would be a starter.
CP, grab an ELM327 for about a tenner, download EOBD Facile (free) on your laptop or netbook and you have realtime monitoring...

Works on loads of other motors too, best tenner you'll spend in a while.

My 327 is an ancient tin box, all the new ones seem to be fancy plastic coloured and some are Blue tooth affairs. I'd go for a wired version myself, there are so many revisions and plenty of fakes (I'm sure mines fake but it works great) so just make sure you buy one from a UK seller.

I'm certain the Fiat specific one is great too, but it seems you need to spend a bit more on connectors and such.
i have an elm thing i used to use fiat ecu scan but that was on mu since departed dell now use a macbook pro :( not many options on osx we do have other windows based laptops in house but the dell had a full version on ecu scan :(
There is some stuff for Linux. You could clear Apple's horrible mutation of Free BSD off and put Linux on. Alternatively, pop a Virtual Machine inside OSX and run Windows from that. See the Open Source option here.
will just get an old laptop out tomorrow need to buy a windows disk soon and might run it on bootcamp my desktops running linux at the mo (y)