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mr_caarl · Joined: 21 Mar 2019 Posts: 8 Location: Sweden

I found an empty wire connector but no stray wires near by.

Probably a stupid question but does anyone know what the connector is for?

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!tom · Posted: Thu Jan 23, 2020 7:54 am Post subject:

It would help to know the particulars of your car, as things such as this changed depending on the model year of the car.

It might very well be a fuel pump relay cutoff switch, which causes the fuel pump to shut off if the engine stalls. One use case for such a feature is to shut off the fuel pump in case of a crash.

My recollection of when I was looking into this feature on my car is if the connector is disconnected, the fuel pump will run regardless of if the engine is running or not, but if it is connected, the fuel pump will only run if air is deflecting the air flow plate.

Might be different for your car...
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mr_caarl · Joined: 21 Mar 2019 Posts: 8 Location: Sweden

Sorry, I should have given more details.

The car: Porsche 924 n/a, Euro version -79.

I checked the fuelpump relay wiring. The "cut off switch"/on-signal for the relay is wired to the ignition coil (same connector as the tachometer). This seems correct and the fuelpumps are running as expected so the connector in the image must be for something else?

The only stray/loose wire i can find in the engine bay is the signal wire for the engine temperature indicator (the indicator is obviously not working). But the wire is located at the back of the engine bay close to the firewall and the connector more at the front. So i assume its not the connector for the temp gauge?

924RACR · Posted: Thu Jan 23, 2020 11:01 pm Post subject:

That's definitely the fuel pump cutoff switch, but for the early cars; makes one wonder if perhaps the air flow meter was swapped in from an earlier car at some point.
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mr_caarl · Joined: 21 Mar 2019 Posts: 8 Location: Sweden

I wouldnt be suprised if the air flow meter has been swapped at some point.

Thanx for the help!

Moving on to the next problem. Does anyone have a good picture or description on where i can locate the engine temperature sensor (not the cooling fan sensor)?

I found the wire in the engine bay close to the firewall but i cant find the sensor or where the wire should connect.

Ozzie · Posted: Sat Jan 25, 2020 7:05 am Post subject:

on housing the rear water hose comes off the back of motor, looks like a nail head
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