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Racso59
Joined: 30 Mar 2024
Posts: 10
Location: France
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 Posted: Sun Jul 28, 2024 9:03 pm Post subject: 924 EFI With ITB electrical problems |
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Hey, yesterday i started for the first time my efi itb 924. Everything’s working absolutely fine apart from one thing. The car doesnt stop when i turn and take the key off. The ECU and the ignition are powered by a main relay, 30 is plugged to 12v, 87 goes to ecu and ign, 85 is Powered by 12v at ignition and at start (black wire from the fuel pump relay), 86 is the ground from the FP relay.
I took the OE FP relay out and replaced it with a 4 poles new one. 30 and 86 are 12v always, 87 goes to the fuel pump and 85 is a ground sent by the ecu to activate the fuel pump.
I started investigating and discovered That the black wire from the original fuel pump relay stays at 12V Even when I turn the key to stop the car.
Does anyone know something that I could have missed ?
Thanks a lot |
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924RACR
Joined: 29 Jul 2001
Posts: 8889
Location: Royal Oak, MI, USA
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| Posted: Sun Jul 28, 2024 9:27 pm Post subject: |
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What ECU are you using for the EFI?
Usually the ECU would control the fuel pump as well; in my Microsquirt installs, this is the case, a separate relay is used to power a fusebox which provides power to the fuel pump, ignition, fuel injectors etc.
In this configuration, the relay ground is provided by the ECU when the ECU is happy with the engine turning/cranking, so all are switched off after.
This sounds like it matches your situation, except that maybe you didn't check that your ignition signal is indeed that? Sounds like you took that from the fuel pump relay, which actually is hot all the time and needs to be replaced with the correct lead from the ignition switch?
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Racso59
Joined: 30 Mar 2024
Posts: 10
Location: France
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| Posted: Sun Jul 28, 2024 11:09 pm Post subject: |
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My bad, my explanation was a bit confusing.
I’m using Maxxecu street. The ecu and ignition are powered by a 4 poles relay. This relay is controlled by the black wire originally used for the fuel pump relay, so it’s a 12v when the key is on ignition.
The ecu controls the new fuel pump by provinding a ground |
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morghen
Joined: 21 Jan 2005
Posts: 9014
Location: Romania
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| Posted: Mon Jul 29, 2024 1:37 am Post subject: |
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Remove the charging light bulb from your dash, see if that cures it.
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Supercharger and EFI kits
https://www.the924.com |
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Racso59
Joined: 30 Mar 2024
Posts: 10
Location: France
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| Posted: Mon Jul 29, 2024 7:35 pm Post subject: |
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I didnt believe it but it worked, Thanks a lot.
Now i need an explanation |
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mrborrie
Joined: 09 Jun 2021
Posts: 29
Location: Netherlands
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| Posted: Mon Oct 28, 2024 9:56 pm Post subject: |
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| Racso59 wrote: | I didnt believe it but it worked, Thanks a lot.
Now i need an explanation |
yeah this guy knows whats up with that stuff 
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760 Turbo |Volvo 360 cup|Volvo XC90 04|Porsche 986S|Porsche 924 79| |
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morghen
Joined: 21 Jan 2005
Posts: 9014
Location: Romania
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| Posted: Mon Oct 28, 2024 10:21 pm Post subject: |
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Get one of those LED replacement lights and install that one.
It will take you a few tries to get the polarity right but once done, your charging will work and the car will stop.
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Supercharger and EFI kits
https://www.the924.com |
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