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S3 ECU on A3 1.8T?

Discussion in 'A3/S3 Forum (8L Chassis)' started by 9-Points&Counting, Jul 25, 2012.

  1. 9-Points&Counting
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    9-Points&Counting Member

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    Hello.

    I've just bought an 03 plate, A3 8L 1.8T but have still got my 2000 plate, 8L S3 with a Revo map in it.

    Does anybody know if I can directly swap the ECU's?

    And if you know that, you may know if I can also swap the injectors and the forge DV to carry on getting all the fun of the fair from my S3 :laugh:

    Cheers.
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  2. ads1377
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    ads1377 Member

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    I cant see anything wrong with the Forge DV as this is a straight swap for the original.

    Not sure about the other things
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  3. <tuffty/>
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    <tuffty/> Badger 5 Edition Staff Member Moderator

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    Nope... an S3 ecu/map can't be used for several reasons.. the S3 ecu you have will most likely be from an APY so not even physically the same type of ecu...

    You wouldn't be able to use a wideband ECU and map from a later S3 either as it will be coded for completely different hardware and the S3 has sensors the A3 doesn't have..

    <tuffty/>
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  4. Broken Byzan
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    Broken Byzan Photographic Moderator Staff Member Moderator

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    Why not just drive the S3, much easier than swapping bits around, even if they were to fit,lol
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  5. beachbuggy
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    beachbuggy Well-Known Member

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    Knock sensors, maf, injectors, coilpacks, lambda sensor are all going to different, if you fitted the turbo, injectors, maf, knock sensors, loom and lamfa from the s3 onto the a3 then yes it would work.
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  6. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    why would the knock sensors be different?

    I planned to use my 058 AJL knock sensors with a AUQ wideband ECU...
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  7. beachbuggy
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    beachbuggy Well-Known Member

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    They are different frequency or something, when I upgraded my APY to BAM the knock sensors didn't register CFs. Barks found the same. I changed them over and all was good.
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  8. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    hmm...

    need to compare part numbers and see whats what.

    I believe the APU runs ME7.1 and uses the same sensors as mine, will need to see what the AUQ uses.
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  9. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    Ok seems to be some sort of narrowband/wideband split.

    APY and AGU use the same sensor

    AUQ and BAM use the same sensor

    One would imagine that means my ME7.5 ECU is going to want the later sensors from an AWT or B6 motor of some description.


    How come i've never heard of this issue when folk convert from narrowband to wideband?
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  10. beachbuggy
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    beachbuggy Well-Known Member

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    Well i'd imagine that most people that do this wouldn't bother to look at CF's maybe? I only took notice as I was mapping the ECU and thought it odd nothing showed on the CF's...

    Now you know though :)
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  11. Barks
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    Barks Member

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    The knock sensor wiring on pre 2000 APY is reversed to a post 2000 apy. All wideband ecus have the later apy wiring

    Therefore if you do a wideband conversion on a pre 2000 apy the knock sensors are reversed for the new wideband ecu and no knock is sensed, (I have a later APY and reversed mine to prove and no knock was sensed).

    I have yet to fit the new (none tail type) knock sensors to prove if there is difference in the measure knock therefore CF.
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  12. badger5
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    badger5 RIP S3dave Site Sponsor

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    its windowed knock sensing so this would kinda make sense (the no workie bit if reversed), Comparing knock voltages would be another measurement to see if levels are perceived as being the same I guess
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  13. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    cant you just reverse the wiring in the harness to suit?

    And by reversed do you mean the channels have been swapped over, or that the polarity on the sensor is backwards?
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  14. Barks
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    Barks Member

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    Yeah, I am going to compare logs and compare the knock voltages between the old and new style sensors, to prove if there is a differnece in design on the actual sensors.

    The knock channels are swapped over between the versions, the plugs are identical so it can be changed at the by swapping over the plugs.
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  15. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    Ok, a very quick look suggests that the ME7.1 APU harness i have is wired the same way as the later ECU's, so might not be a problem at all :)

    I'll post the pinouts shortly.
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  16. 9-Points&Counting
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    9-Points&Counting Member

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    Cheers mate, an nice clear answer for a change :icon_thumright:
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  17. <tuffty/>
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    <tuffty/> Badger 5 Edition Staff Member Moderator

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    Welcome... all my answers are clear :p

    <tuffty/>
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