Sensors on the block

[Ross]

What sensors & switches are attached to the block? I'm planning on putting the RS2 engine back in and want to be sure I have everything for this weekend...

So far, I'm re-using knock sensors and the ones by the flywheel - all replaced in the last few years and in good condition. I've replaced the two on the water rail with near-new ones.

There's a chunky oil pressure sender that I have a new replacement for. Have a new thermostat too.

I'm sure there were a couple of very corroded two-pin sensors on the block, what are they and what else am I forgetting?

[S2central.net]

theres the two dopey pressure sensor/swicthes on block near the knock sensors - is that you ones you are talking about ? The bigger cylindrical one is 0.3bar switch and pressure sender. The little dippy white body one is 1.8bar switch

there is also oil temp sensor at the oil pump housing that you have not mentioned

[Ross]

Thanks Paul - that's what they'll be, 2x oil pressure sensors. The 0.3bar is the one I have. Guess I need another then!

The temp sender is fine, didn't realise that was on the oil pump. I have a new pump and temp sender then - or at least with only 200 miles on it. I feel like I'm getting a bit of good value out of my old quattronics engine build now

[UrS4boy]

Something like this help?

[Ross]

That'll come in helpful, even got a part number

[Billman]

The adu engine has the upper oil pressure switch with the E?

[UrS4boy]

The adu engine has the upper oil pressure switch with the E?

The location of the pressure switch is not necessarily the same as the diagram I posted. (See photo below). However, yes the oil pressure switch is 056919081E which is very common across the older Audi line. It is a 1.8 Bar M10x1 1 pin White (as opposed to the black UrS6 switch).

On a related note, according to my friend Kate, she says the oil pressure gauge sender PN for the ADU and ABY is 035919561, not 034919561 for the AAN. The 035919561 is a 0-5 Bar sender with a 0.3 Bar switch but the threads are M10 x 1. The 034919561 for the AAN has M16x1.5 threads. Probably something to do with the location of the oil check valve behind the gauge sender in the AAN.

[Billman]

The sensor is as on the picture and on the diagram on mine. I have seen an AAN recently where they where in the opposite direction. Switch on top and sender bottom. The second part number on the diagramm for "urS6" is apparently lower than 1.8 bar.

I bought one 056919081E for 5 euros today because my old one leaks.

[UrS4boy]

AAN Oil Pressure Sender, Switches and Check Valves

The sensor is as on the picture and on the diagram on mine. I have seen an AAN recently where they where in the opposite direction. Switch on top and sender bottom. The second part number on the diagramm for "urS6" is apparently lower than 1.8 bar.

Yes, the UrS6 black pressure switch is 1.4 Bar, not 1.8 Bar like the white UrS4 switch.

I don't know about the ABY and ADU but the AAN has an oil check valve in the block, behind the larger threaded oil pressure gauge sender, as documented here:

http://forums.quattroworld.com/s4s6/msgs/96161.phtml

[Billman]

all engine have this. Some screwed with that torx some other with a spring.

[UrS4boy]

all engine have this. Some screwed with that torx some other with a spring.

I am sure they do. I am just confused as to where the check valves are on the ADU and ABY if both of them use M10x1 sender and switch threads. (The AAN M16x1.5 threaded boss gives lots of room to install the triple square-socket headed 077103175B check valve)

[Billman]

they are under the pressure switch

[europeanme]

The location of the pressure switch is not necessarily the same as the diagram I posted. (See photo below). However, yes the oil pressure switch is 056919081E which is very common across the older Audi line. It is a 1.8 Bar M10x1 1 pin White (as opposed to the black UrS6 switch).

On a related note, according to my friend Kate, she says the oil pressure gauge sender PN for the ADU and ABY is 035919561, not 034919561 for the AAN. The 035919561 is a 0-5 Bar sender with a 0.3 Bar switch but the threads are M10 x 1. The 034919561 for the AAN has M16x1.5 threads. Probably something to do with the location of the oil check valve behind the gauge sender in the AAN.

as per ususal Dave, a picture paints a thousand words....

[mcandmar]

Interesting about the S6 having an M16 sensor, any S2's i have seen had an adapter piece converting to M10.

The small sensor is also leaking on mine, looks like a rad out job to get at it

[UrS4boy]

Interesting about the S6 having an M16 sensor, any S2's i have seen had an adapter piece converting to M10. The small sensor is also leaking on mine, looks like a rad out job to get at it

The UrS6 oil pressure switch 068919081 (black, 1.4 Bar, is M10x1)