If your Porsche Cayenne is leaking coolant, chances are the coolant pipes located in the “V” of the engine beneath the intake manifold are to blame.

What exactly is the problem?

The early Porsche Cayenne V8 models fron 2003-2006 (manufactured between January, ’02 and December ’06) came from the factory with plastic coolant tubes that are now known to be defective and prone to premature failure. There are a handful of theories speculating why they tend to fail early and in reality, there is probably a little bit of truth to each one. To begin with, it may have something to do with the pipes being located in the “V” of the engine, beneath the intake manifold. Encased in that way, the pipes are subject to heat soak from every side and even at speed there is very little air-flow through that area. It’s a very common problem on these vehicles and there is a solution which we will get to shortly, but first let’s take a look at some of the “symptoms of leaking coolant pipes” that you, the owner, can be on the lookout for.


Leaking original plastic coolant pipes. (Click to view larger version in new tab)

“How to tell if the plastic coolant pipes are leaking?”

The most obvious sign that the original plastic tubes may be leaking, and the simplest, is the presence of coolant on the ground or garage floor. The way you can distinguish between coolant and some other type of fluid on the ground (such as an innocuous pool of A/C condensation, for example) is the color. Porsche coolant, unlike most other vehicles, is pink in color so the presence of a pink or red-ish liquid collecting on the ground, especially after a long drive, is a strong indicator of a coolant leak. Counter-intuitively, problems with the starter motor can actually be another possible symptom of coolant leaking from this particular location. Because of where these pipes are, when they leak coolant it first fills up the valley in the center of the engine before appearing anywhere visible. Once that valley has filled up, the first place it usually spills is the rear of the engine and down onto the starter. This can damage the starter, causing starting issues and, if left alone, it can eventually ruin the starter altogether.

The Solution: “When should I replace the original coolant pipes in my Porsche Cayenne?”

Fortunately, Porsche has updated these parts since their original manufacture and this update is now the standard repair for the leaking plastic originals. The updated kit includes new cast-aluminum pipes (pictured below) to replace leaky plastic ones.


Updated aluminum coolant pipes for V8 Porsche Cayenne. (Click to view larger version in new tab)

But what should you do if your vehicle isn’t showing any of the symptoms mentioned above but still hasn’t had the update performed? The rate of failure of the original plastic pipes means it is less a matter of if they will leak and more a matter of when. Couple that with the potential that an unnoticed coolant leak has to cause significant damage to the starter or worse, an overheated engine, it is recommended that any V8 Cayenne from the affected model years that still has the defective plastic original pipes have this update performed as a prudent preventative measure, regardless of whether or not they have started to leak yet.

Case in Point:

One of our customers recently brought their 2005 “Porsche Cayenne S” (pictured below) in to us after noticing “pink liquid dripping onto the ground” beneath the engine and the “low coolant level light” come on on the dash. It didn’t take long to confirm our initial suspicions that the plastic coolant tubes were the culprit. In this instance due to the mileage of the vehicle, this customer wanted to err on the side of caution and had us replace the water pump (pictured below), serpentine belt, and thermostat in addition to installing the updated coolant pipes. By the next day, we were all finished and our customer was back on the road, leak-free and with peace of mind.


Updated pipes installed. (Click to view larger version in new tab)

If you aren’t sure if your Cayenne has been updated with the new aluminum pipes, we highly recommend bringing it in to see us and one of our “qualified Porsche repair specialists” will be happy to help. Give us a call at 972-317-4005 to set up an appointment today!