C3 Engine swap - mystery sensor

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jcmnz
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Joined: 02 Aug 2022, 04:00

C3 Engine swap - mystery sensor

Post by jcmnz »

Hi, after a bit of reading I'm hoping to replace a 5FS/EP6C engine in a 2011 C3 with a 5FW/EP6 engine from a 2008 207. All going ok so far, but the 5FS has a sensor in the sump area that the 5FW doesn't. Can anyone identify this please:
5FS-Rear Sensor.jpg
Worse case scenario, I may have to change over that section of the crankcase - not that keen to disturb bearings.
These cars are so much easier to extract the engine and trans on than say an older car like a 406. With the front grille and associated bits off, the whole assembly glides out easily. And no intermediate driveshaft bearing :)

Thanks in advance
jcmnz
Posts: 3
Joined: 02 Aug 2022, 04:00

Re: C3 Engine swap - mystery sensor

Post by jcmnz »

IMG_20220802_213004790.jpg
Better picture tonight:Image
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GiveMeABreak
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Re: C3 Engine swap - mystery sensor

Post by GiveMeABreak »

Although the EP6 and EP6C engines are similar in output, they have different oil pressures. The difference between the engines are the Euro standards (Euro 4 and Euro5). So this will also likely result in different monitoring of the engines including sensors that may be present on one engine and not the other.

Read this post which has covered this subject before:

viewtopic.php?p=693449#p693449

So you may have issues with the engine ECU too if it is not getting the correct inputs.
RichardW
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Re: C3 Engine swap - mystery sensor

Post by RichardW »

I think it's not actually a sensor, but in fact feeding a solenoid on the oil pump, presume the ECU has control over the oil pressure somehow.
jcmnz
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Joined: 02 Aug 2022, 04:00

Re: C3 Engine swap - mystery sensor

Post by jcmnz »

Thanks - that's it; I've found pics of the controlled oil pump with that cable hanging out. I wonder if the ECU tries to servo control the oil pressure or just open loop output to the pump solenoid. DiagBox might show me if there's a linear oil pressure reading; if not, then I can just remove the solenoid and keep it on the outside of the 5FW engine. Worst case - I have to swap over the lower crankcase and controlled pump. I'm always scared to disturb crankshaft bearings...but maybe I can swap the shells over to the 5FS casting without any problems. It seems like a lot of messing around, but finding a 5FS was proving difficult/expensive!