cjcomeau

I can use some help. My 996 is leaking coolant from under my expansion tank. The tank was replaced less than 5k miles/11 months ago so I don’t believe it is cracked…not the cap either. So here is my situation. On the underside the tank there is a connector/sensor. I presume it is a temp or low fluid sensor. The tank appears to be leaking from that point. The connection is loose. It can move approx. ¼ turn by only touching it. Should it be loose and is this a likely culprit? How to fix (assuming pull tank out)? I will post pics soon.


The car is a 1999 996 cab tip 114,000miles

Thanks,

Calvin

F/S 1999 996 cab tip blk/blk $23,900

cjcomeau

pics

cjcomeau

pics again

It is the connection w/ the wires near middle of pics

Thanks for your help.

Calvin

redridge

do you have low coolant light on?' does it only leak under pressure? whatis the last 2 # on your cap?

1/4 turn is alot if you're just touching it.....

might have to take the tank out and investigate...

cjcomeau

Low coolant light is not on. Only leaks under pressure. A few drops last week. A few ounces yeasterday.

Looks like I know what I am doing this weekend.

Calvin

Guybrush Wilkinson

I have the same problem with my original expansion tank. Only leaks with pressure but not every time I drive the car. Just occasionally.

I doubt the "sensor" is a low fluid sensor. Even though the expansion tank is completely empty, the low fluid -light does not come on.

I have noticed, that the expansion tank low - full indicator is extremely sensitive about how level the car stands on the ground. A tilt of just a degree or two affect the measurement a lot.

I have never had a problem with overheating though - even though I have had to add fluid to the system.

Ryan C

That sensor is the low level light indicator. It goes in the expansion tank by turning it 1/4 turn. It has detents that hold it in. It doesn't acutally go through to the inside of the expansion tank. There's a floater on the inside around the area that the sensor goes in. That thing being loose has nothing to due with a leak. It's possible that the tank is just leaking again. They usually crack on the back underside, so maybe fluid is just going to the lowest point.