gunlover05

Guys, I have been suspecting a cold start problem (when it is only really cold) on a possibly old CHT sensor....I don't have service history @ PO, but i took this pic today @ engine compartment when i was changing my spark plug wires....i'm pretty sure i see 2 small white wires inside of the clear covering...is this already the "upgraded" 2 wire CHT sensor versus stock single wire? hoping it is...

der Mond

I replaced mine last summer with an updated one from Pelican. It was obvious looking at the new one with transparent sheath that it had two wires. There really was no question. However, I no longer remember what the old one looked like. Maybe someone else can verify.

J. Brinkley

if it has two prong connectors on it it's the udated one, if only one then it's the older one.

der Mond

I beg to differ...the old sensor wire on mine had a two-prong connector despite there only being one actual wire. And it was for sure the old sensor wire because it required the older sized socket to unscrew from the head, the new sensor requiring the new sized socket, which I modified with a dremel grinding wheel in order to be able to tighten it obsessively properly with the wire attached! So the new two-pronged sensor clips right in to the existing fitting shown in the photo above. I have no idea why there was always a two-wire connector from the Motronic box to the sensor when the old sensor had one wire, but I'm glad! Makes the upgrade easier, which by the way goes much better if the left rear shock is removed.

gunlover05

so do you guys think this is the upgraded 2 wire sensor? I do see two wires in there, but don't know what the original wire looks like...

g-50cab

It's really easy - pull the plug off the top right hand wire - the white one - if there is one prong it's the one wire - if it's two prong then it's the newer version - and probably would not need to be replaced.

BTW it looks in pretty good shape - so I would guess it's the updated version from the picture.

der Mond

If you do see two wires in there, it is the upgraded one, so no worries. I agree with Jeremy that it looks like the new one from the outside. But I also reiterate that my old one-wire sensor had a two-pronged connector, as though the Motronic box was prepared for a two-wire option, or who knows, maybe Porsche didn't want to spend extra bucks spec'ing a special one-prong fitting for that one and just left one prong dead? So you guys who may think that if you see two prongs when you unclip, you have the upgrade, better double-check. The old one requires a 13 mm socket to unscrew from the head but the new one is larger diameter and requires a 14 mm.