What are these plastic parts floating in coolant tank?
 

2004 Boxster S, 98K miles, new to me in the last few weeks. Noticed coolant was a smidge below the min line, and I thought I had checked that before, so I dutifully pulled up the trunk carpet to inspect the tank, look for evidence of leaks on the floor, etc.

Quite clean in the floor. I don't think this tank has been leaking. The tank itself looks good, not yellowed, and shows part number 996.106.(7?)47.09, made by Geiger Technik. Pelican lists the 996.106.147.08 as the tank for this car. Perhaps it has been replaced recently?

Peeked down into the tank itself before adding a splash of distilled water, and saw a plastic part floating down there in the coolant... poked that around with a probe to see what it was... it looks just a bit too big to be able to come up and out through the filler neck... which makes me think that part was actually born there and belongs there somewhere. But it seems to be loose. And it has a friend. Both are loose, untethered, as far as I can tell. I can roll them around with a probe.

Larger floating plastic piece on right in this pic, smaller clear plastic cap-looking piece to left.

What are these? I haven't seen a new tank up close, so I don't know what's in there. Perhaps the coolant level float (if there is such a thing) has come loose? Any clues appreciated.

http://986forum.com/forums/uploads02...1572222545.jpg

For anyone else who comes by with the same question: I visited an indy shop. They said coolant level sensor parts broke loose in the tank. Looks to them like the tank is original, but as good as it looks (not yellowed, no leaks, 15 yrs old), this bit has failed. Gotta watch coolant level carefully until I replace the tank... presumably the coolant level light won't work if this sensor is not working.

Hummm....not sure about the accuracy of that reply. Typically the sensor is NOT in the tank....rather it sits in a channel molded into the bottom of the tank. If it needs to be replaced it can be pulled without ever draining the tank. The sensor does not use a "float" inside the tank, it's purely an electro magnetic wired sensor. It DOES NOT SIT IN THE TANK http://986forum.com/forums/uploads02...1574692761.jpg

It’s dead on accurate.

How do you suppose that sensor knows the coolant level? It can’t see it :D
The float tells the sensor the coolant level via a magnet in the float that the sensor “senses”.

Respectfully disagree.....there is NO FLOAT in the coolant tank.....the senosr simply senses the fluid level by measuring resistance of liquid vs. air (or no liquid). Feel free to point out, on the diagram where the float or sender or magnet INSIDE the tank is.........answer, there isn't one, sorry!

The coolant level sensor does not sit in liquid coolant.
It sits in a tube, isolated from the fluid inside the tank.

The sensor is a magnetic reed switch, not a resistance sensor.

It’s the float ;)

Here you go ;)

http://986forum.com/forums/performance-technical-chat/50904-how-coolant-tank-sensor-works.html

OK....I'm wrong....my error.

Particlewave. Kills. It. Again.

He's one of my three (3) "Go-to" members when I'm in a pinch. I'll do my research... entertain some suggested troubleshooting, corrections, modifications, replacments, repairs... and it always lands on one of the three. Further, they're 99.99% spot on. That saves me some headache and, more importantly, some quid. Me likes the quid.

Happy Thanksgiving!

+++That^^ !

I never argue with pw...it's a losing proposition (coming from one who is decidedly NOT one of the other two!).

He accurately explains all kinds of stuff—hell, he's even hands-on fixed stuff for me that I'd not had a clue about. May he stick around here forever...at least til I sell my Box! :cheers:

Yeah... we know you'll never sell the Box. :cheers:

Thanks @particlewave and @Rob175 for weighing in on my little mystery, now solved!

Yeah, you're probably right about that. With 104k, I might as well go ahead and play the hand I'm holding.. :rolleyes: