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Gram · Posted: Thu Apr 28, 2005 6:23 am Post subject: What's this for?

Underneath my fuel distributor, towards the intake manifold, theres a sensor/switch thing with 2 leads off it (br and white wire with red spots). From Haynes page 306 it looks like a temperature switch altho the lead colours don't quite match. I can't find it mentioned in the text. What is it and what does it do? Any test for it.? TIA
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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)

Smoothie · Posted: Thu Apr 28, 2005 12:34 pm Post subject:

If it's what I think you're asking about, then it is (or is associated with) the "supplementary start valve" -

Gram · Posted: Thu Apr 28, 2005 2:28 pm Post subject:

Thanks smoothie. It's kinda cylindrical..No clue on how to check that it's working.? I might take it off and have a play with it.
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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)

John Brown · Joined: 07 Nov 2002 Posts: 903 Location: Leesburg VA

You can check that it's getting power. Should only happen with a warm car and while the starter circuit is engaged. Note that this piece is only involved in warm starting and so only if it failed open or on would it adversely affect the motor running.

And, I am not sure if this valve 'chatters' or if it is simply an normally closed valve with a metering orifice. Suspect it is a normally closed valve with a metering orifice.

Since it bleeds off the fuel distributor lower chambers I do not think there is any way to measure the fuel pressure changes.
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John
80 931 - #931 44Cup
99 Escalade - tows track cars
gone but not forgotten: original 924.org car - 82

Gram · Posted: Fri Apr 29, 2005 2:14 am Post subject:

Thanks John. Have to admit that's a bit beyond me so I'll check for power and leave it alone

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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)