Mystery wire...

john@byson · Post by **john@byson** » 11 Apr 2016, 08:50

Sorry if this has been done before but I can't seem to find an answer....

Just below and slightly in front of where the the camshaft position sensor wires come from the sender a lead emerges from the cylinder head area and terminates in a 2 pin white male connector. And in my case that it all it does. It is not actually connected to anything. In my admittedly limited experience manufacturers don't usually hang spare leads out of motors but I can find no mention of this & can't see a picture online or in the Haynes manual. Or indeed the Volvo service manual.

Is it a "spare" intended to hook up to something not fitted in an 850T or should it actually plug in somewhere. I can see no corresponding female socket.

The car (1994 850T estate) runs fine.

Post by **kahl** » 11 Apr 2016, 10:06

I can't remember if your car has a PTC on the plastic intake pipe from the air cleaner box to the turbo. The PTC is a two prong fitting. I also recall there is a plug on the air cleaner box. It's been about 10 years since I had my 94 850 turbo.

Post by **theWIFES_S70** » 11 Apr 2016, 10:13

Is it this guy?

Post by **Ozark Lee** » 11 Apr 2016, 18:33

The PTC is a very good guess. It isn't a sensor, it is a heater for the return vent hole on the PCV system and it has no real impact on how the car runs in the short term. The socket where the electrical to the PTC plugs in is pretty well hidden on the intake snorkel just before it enters the turbocharger.

...Lee

kaneelschep · Post by **kaneelschep** » 12 Apr 2016, 14:35

Maybe post a picture? Thats always easy

john@byson · Post by **john@byson** » 13 Apr 2016, 09:55

Pictures always help but without removing the airbox, not easy. These are as good as I could get with a 'phone.

http://www.bysonleather.co.uk/Odds%20&%20Sods.htm

john@byson · Post by **john@byson** » 13 Apr 2016, 10:17

Solved. Marco has it. At some stage someone has swapped out the crank position sensor and left the old unit hanging about in there. The actual unit was JUST visible at an almost impossible angle, tucked up under the assorted cables & "stuff". The lead went down behind the engine upper mount plate and looked as if it emerged from the head area. NOT easy to see exactly what is going on round there

Who thought that was a good idea then ?

Post by **theWIFES_S70** » 13 Apr 2016, 11:07

Oh my gosh, someone left an old crankshaft position sensor in there? I would've cut the connector off if I couldn't get it out. (You never know when you'll need a connector!) That's nuts, though. Glad we figured it out!

Post by **abscate** » 13 Apr 2016, 12:14

john@byson wrote:Solved. Marco has it. At some stage someone has swapped out the crank position sensor and left the old unit hanging about in there. The actual unit was JUST visible at an almost impossible angle, tucked up under the assorted cables & "stuff". The lead went down behind the engine upper mount plate and looked as if it emerged from the head area. NOT easy to see exactly what is going on round there

Who thought that was a good idea then ?

something about leaving an old part on a car is just advanced hackery...thats just wrong...