tkd_hurricane

I'll give a brief background on my car and issue. I bought a used 2004 Cayenne S a few years back.. Within a year, I was the lucky guy who had the plastic coolant pipes crack instead of the original owner. It only had about 50,000 miles on it when I purchased it. So anyways, I bit the bullet and had the replacement pipes put in and had to replace the starter that was ruined by the coolant leak.

So now, my issue is that every time winter comes around, it seems as if I lose coolant. My car was serviced over the summer (July) with all fluids topped off. Obviously the car starts a bit harder in the bitter cold and it takes longer to warm up. I was out of town for a weekend and my car sat unmoved. When I came back it started very hard and since then every time I start my car first thing in the morning, the Coolant Level light comes on. After driving and the car being fully warmed up, if I shut it off and turn it back on, it seems to have normalized. However, upon checking, the coolant is actually a bit low.

I'm not having any overheating or issues arrising from it thus far. But it seems as if I have a slow leak because each winter, I have this same issue. I have a hard start and then the coolant light keeps coming on, and once the car is warmed up it goes away if I restart the car.

However, I let it go for research purposes and If I let it go like this, eventually the coolant light will remain on even after it being fully warmed up.

I don't smell any coolant and it seems to be a very slow leak. Any ideas where the issue could be?

slots

Maybe check this thread:

https://rennlist.com/forums/porsche-cayenne-forum/772567-water-distributor-failure-2008-ctt-50k-miles-2.html

touareg

That thread is only for the newer 957s.

I would start checking for typical european car type coolant system problems.

Make sure your coolant expansion tank is not leaking.

Heater hoses from the block could be leaking.

Air in the system.

This system is pressurized.

seankrider

So the expansion tank definitely cracks on an '04. The caps go bad too.

It could be anywhere, but if it's a slow leak, check to see if you can move the water pump pulley at all. It's almost top center on the front of the engine if you can see the serpentine belt. I forget if you have to take off the intake "Y" to see it. Any play at all means its bad and you need a new water pump (and it will slowly leak out the front until all the impeller blades go, then it will stream coolant out as it wobbles freely).

I'm in the same boat, hunting down a small leak that just became a big leak. So far I've done these two and both were bad. Plus the hose tees in the back for a second time (mine is a turbo), so I'm batting 1,000. Ugh.

Heater hoses and/or the heater itself sounds like no fun, but that my be next on my list.

Anyone have good advice on pressure testing for the DIYer?