Megasquirt Newbie Questions - All the really dumb ones you were afraid to ask!

Discussion in 'Throttle bodies & non-OEM ECUs' started by Mike_H, Apr 27, 2010.

  1. Mike_H Forum Addict

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    More Questions... The more I read, the more confused I get, by seemingly contradictory statements

    5. Main Power Feed and Relay / Relay Board
    - PIN 19 says sensor ground - required for relay board. As I've been told I don't need a relay board. I guess I'll just connect this to earth anyway, but do I actually need it?

    6. Main power relay
    The Rocco already has an ignition live relay in the fuse box, and spare terminals for ignition live connections. Is this good enough for the MS ECU power feed, or will the feed not be clean enough.

    7. Fuel Pump Relay
    I'm confused about whether to modify the wiring around the standard VW fuel pump relay, or whether I need to even wire it into the ECU or just leave it alone. The pump is fed by the existing VW circuitry, but I think the shut-off was controlled by Kjet. Am I risking the pump running on if the engine stops (e.g. in a crash), if I don't wire it into the MS system?
     
  2. Toyotec

    Toyotec CGTI Committee - Happy helper at large Admin

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    Note:
    The MS that Mike has does NOT need a pullup resistor added.
    The MS1 ver 3 pcb, was built to match the RSA diagram and loom without the installer having to mess with the ECU hardware.
     
    Last edited: May 1, 2010
  3. Toyotec

    Toyotec CGTI Committee - Happy helper at large Admin

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    As you have an ABK rail you can split the injectors in groups of 2 and use inj1 and inj2 accordingly.
    Group cylinders 1 and 2 as 'inj1' and cyl 3 and 4 on 'inj2'. Power with "N" on your CE1 fuse box. The base cal is set up on batch fire, but with this grouping you can eventually switch to alternating.


    Use the Audi 2 pin CLT as the base cal is already config'd for bosch sensors. If the IAT is a Bosch unit, again the base cal is already setup to match. Follow the diagram and use one of the 5 long black loom wires to earth the sensor


    G69 TPS
    Pin 1 5v for TPS ref
    Pin 2 middle pin would be signal return to MS
    Pin 3 Earth ( one of the 5 black wires on the RSA loom)

    4. Distributor
    - Pin 24 on the ECU is the Tach signal to the ECU - anyone know which pin on the VW 3 pin hall sender that is?

    G40 hall sender
    Middle pin "0" is the hall return, power G40 with tach reference 5v on pin 3 "+" (red/black) use one of 5 black loom wires to earth the hall on pin 1 or "-".
     
  4. Toyotec

    Toyotec CGTI Committee - Happy helper at large Admin

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    Find the short black wires ( pins 7 to 11) on the loom and connect to a 2.0mm thick wire lead that is long enough to head for the battery earth. That's it.

    Any switched +ve 12v output from this relay should be fine.

    You need to earth this relay to turn on the switched 12v to the pump or "N" injectors.
    Use pin 37 on MS ( blue wire with F/PUMP) to provide this earth.
     
  5. drunkenalan Paid Member Paid Member

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    this all sounds v ery familiar, i was here about a 3 months ago!, still its great when it all works
     
  6. Toyotec

    Toyotec CGTI Committee - Happy helper at large Admin

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    The smell of rich hydrocarbons , and anything else that burns off, when it first fires fill a small space as a shed , is priceless!:lol:
     
  7. Mike_H Forum Addict

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    What's the advantage of splitting it? I've got a batch fire loom in place, so I'm tempted to leave that for now, unless there's a good reason to change.

    Yes, it's a Bosch job from a BMW.

    Gotcha - willdo


    So the middle pin goes to the ECU? Red/Black goes to the coil +, so that can stay there?


    Ref using the long black earths to the ECU - does that get a cleaner circuit than going through the body then? I was a bit confused by the differences between the wiring diagrams, but I'll change to that. Assume it doesn't matter which one I use then.

    Just as an aside, The RSA wiring diagram with the loom has the long earth wires as 12-16, but actually they're in 15-19 on both the looms I've got.
     
    Last edited: May 1, 2010
  8. Mike_H Forum Addict

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    Ant, thanks for the info. I don't really understand the diagram though, as I'm trying to splice into the VAG wiring, rather than build a new loom. I probably don't know enough to recognise where your example is applicable, Vs different from mine.
     
  9. Mike_H Forum Addict

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    Roger, willdo.


    I'll go and check this one. I think the relay terminals are different.
     
  10. Mike_H Forum Addict

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    Shame you didn't ask all the questions on the forum - It would have saved me a load of typing :lol:
     
  11. Toyotec

    Toyotec CGTI Committee - Happy helper at large Admin

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  12. Mike_H Forum Addict

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    I think I'm more confused now :lol:

    I remember there being a post before about wiring the MS into the TCI Unit, so I'll go and look for that.

    I don't know what a G40 is, other than a supercharged polo. Is that the TCI unit?


    Also re-reading the previous posts, I'm not sure I understood this correctly.
    Is a G69 a std 3 pin TPS?
     
    Last edited: May 1, 2010
  13. Toyotec

    Toyotec CGTI Committee - Happy helper at large Admin

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    "G40" in this case relates to a hallsensor on a VW electrical diagram, similar to "G28" relates to the cranksensor and "G70" MAF sensor.
    Your hallsensor is integrated in the distributer and should be labelled with +, 0, - for the pins.
    "G69" is the term for the Audi TPS as seen on a 3A, 9A or 7A engine.

    MS to the TCI-h unit is somewhere in my 8v MS thread and repeated on Brookster 2.1 16v thread.
     
  14. Mike_H Forum Addict

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    Thanks Eddie - that's a big help. :thumbup:
     
  15. drunkenalan Paid Member Paid Member

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    and i had similar issues.
     
  16. drunkenalan Paid Member Paid Member

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    it was after 3 by the time i managed to get to sleep that night, i was buzzin in more than once sense!
     
  17. bens_cab Forum Junkie

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    i remember going through all this with my mk1 without the help of toyotec i dont think i would have done it and that was nearly 5 years ago now i think god time flys lol

    it doesnt matter how much you read up on all the bits you need to do it just takes time for it to go in then all of a sudden it just clicks and you know
     
  18. HidRo Forum Member

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    So, I have another question!
    Where can I buy MS cheap from the UK or Europe?
    I would like to avoid the customs tax from importing from the US.
     
  19. tshirt2k

    tshirt2k Forum Junkie

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    I got mine from Bill Shurvinton. Does Glens garage kits and also supplied RS loom For a V good price without the taxes.
     
  20. HidRo Forum Member

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    Will ping them!
    THanks!
     

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