what does this sensor do?

[drainsurgin]

I have a 92 td 1.6 jetta . There is a sensor between the puck on crankcase vent and main air inlet to turbo . Can anyone tell me its function. It is shaped like a d inside and looks copper in color.   thanks c

[Vincent Waldon]

It's actually a small heater in-line with the vent line for crankcase fumes... designed to keep frost/condensation from forming in that particular pipe.

I've seen many many many diesels in my travels and have *never* actually seen one connected... perhaps an option for colder climates than Edmonton... although some days that's hard to imagine.

[Black Smokin' Diesel]

I had one connected in my 87 TD. I have no idea if it's actually useful since the PCV pulls hot air from the engine.

[Jettage1]

My 92 Jetta Eco has one connected.  Don't know if it helps anything or not.  Don't even know if it works...or what tells it to work.  Heck, maybe it's always powered.  Someday when I am REALLY bored I'll get out the multimeter & see.  But I doubt I'll ever be that bored   

Besides, I need to figure out a new routing for my air intake tube, & it may mean getting rid of that section of pipe anyway...  Though I will probably still try to tee in the crankcase return somehow.