Electrical & Lights LPG conversion, fuel gauge issue

Discussion in '8th Generation (2008-2015) [Acura TSX]' started by Meindert, Saturday 19th Jan, 2019.

  1. Meindert Junior Member ☆ ☆ ☆ ☆ ☆

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    Hi,
    Just had LPG conversion installed, and observed that the petrol fuel gauge still acts as if the car was driven on gasoline- while is it certainly is consuming LPG. First hunch is that the in dash fuel gauge calculates remaining fuel level from boardcomputer data. After refueling (few liters) it reads the actual level (as it did before the conversion). Can anyone confirm this, an knows how to trick it so level will reset EG every engine start?
    I'm thinking of a relay that shorts the in tank fuel for a short period after engine start with a certain resistor value so it sends 'full' level to the boardcomputer. Anyone done this? Or similar?
    Regards,
    Meindert
     
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  2. DrSam Club Moderator Club Staff

    United Kingdom Sam Birmingham
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  3. SpeedyGee Club Manager Club Staff

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    Yes, I have.

    On the 7th Generation Accord, there is small gauge black earth wire on the tank level sensor. If you put a switch in to break this connection to earth and then start the car, the car starts and the orange "low fuel" light, starts flashing. You then flick the switch back over (so the earth wire is complete again), within 30 seconds or so of doing this the ECU re-reads the tank value and thereby resets the fuel level.

    This is a manual process that you can follow whenever you want to reset the fuel gauge.

    It works a treat on the 7th Generation Accords, I assume it should work just as great on the 8th Generation.

    I actually make the circuits a little more complicated than described above by using a relay and an illuminated switch so you can see when you have left the switch on.
     
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  4. Meindert Junior Member ☆ ☆ ☆ ☆ ☆

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    Thanks! Will try this when temperature gets above zero C..
     
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  5. Meindert Junior Member ☆ ☆ ☆ ☆ ☆

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    Tried this, behaves exactly as you described. One catch, the harness contains 4 wires, cutting the black one results in fuel pump cut-out (i think) hence- no engine start.. The purple one is the one to go. Will check tomorrow if fuel gauge and remaining km's for refueling will reset.
    Ordered myself a 10s delayed-on relay on ali, so procedure will be automatically performed on every engine start.
    Thanks again!
     
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  6. SpeedyGee Club Manager Club Staff

    England Speedy Birmingham
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    On the 7th Generation, there was a thicker gauge black wire and this thinner gauge black one. Cutting the thicker gauge one cut the fuel pump but it worked fine on the thinner gauge black wire.

    Noted, cheers.

    Yeah, I bought some but never got round to implementing one, as these weren't my cars I had done the work on. Please do report back on how you get on with installing that.

    Welcome :Hey:

    Do hang about though (on the forum), don't be a stranger :Smile:
     
    Last edited: Sunday 20th Jan, 2019
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  7. Meindert Junior Member ☆ ☆ ☆ ☆ ☆

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    Will do!
     
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  8. Meindert Junior Member ☆ ☆ ☆ ☆ ☆

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    Update: Built in the time relay. Took supply from the back of the 12V accessory outlet in the boot. Works perfect!
    - - - Updated - - -
    Btw, it's doing about 28-32 MPG on normal driving. Quite reasonable i think.
     
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  9. SpeedyGee Club Manager Club Staff

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    Good work @Meindert :Thumbup:
    - - - Updated - - -
    Which delay timer did you use? Do you have a link?
     
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  10. Meindert Junior Member ☆ ☆ ☆ ☆ ☆

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  11. SpeedyGee Club Manager Club Staff

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    Ah yes, nice and easy solution :Thumbup:
     
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