CaptainGSR

Does anyone have a photo of its location?

I have a 9PA1. 2008 GTS

Cheers,

CaptainGSR

I was told that it is on the back of the engine block, unlike the earlier v8s.
I am trying to find out if I can access it without removing the whole intake manifold.
I have intermittent coolant temperature readings (zero or twelve o'clock).
It started a week ago. It usually works fine after I shutoff and restart the car.
Yesterday, it finally threw a code while driving on the freeway. I did not buy the durametric tool yet, but it is a bit obvious that the code is related to the coolant temp. The engine works fine. The check engine light is steady.

Anyone? It should be the same location on all 2008-2010 957 DFI Cayenne S/GTS and maybe Turbos...

k722070

center of pic is wire harness with the front of the plastic wire guide removed, obviously intake is removed.
lookers left of the wire harness, behind the plastic wire guide at the base of the visible aluminum(stamped A 1598 upside down) is where the temp sensor lives on my 2008 gts.
I had to remove the rest of the plastic wire guide to reach the sensor.
time consuming but not difficult.

pelican parts cayenne tech articles has more pics of the procedure.
I used the airlift product as mentioned in the tech article to bleed the coolant system.
very cool product, fun to use and almost made the whole thing worth the trouble.
http://www.pelicanparts.com/techarti...eplacement.htm

CaptainGSR

Awesome! Thank You,
I am guessing the intake has to come off in order to remove the wire guide?

(It is between -5c and -10c where I live. I was trying to avoid working on the car for too long. I'm also worried about breaking plastic parts with such temperatures...)

k722070

even with the intake gone I couldn't reach it until the plastic wire guide was removed.
squeeze a hand back and try to remove the sensor wire connection, then fit a 22mm socket and some sort of extension, maybe it could be done.
it is below the tank so remove as much coolant as possible first.
the cel code is specific to the temp sensor so you can know for sure before trying to remove it.

removing the intake is kind of easy, pelican has the instructions. get a long t-handle T40 to make the job easy.
the only difficult part of installing the intake is lining up the gaskets and fitting rear the vacuum line at the same time.
with the intake gone you can check the coolant line in the V of the engine for leaks.
also you can check the glued fitting on the rear of the coolant distributor that sometimes fails.

deilenberger

And if you're smart - you'll slather the joint of the fitting to the manifold with JB-Weld..

CaptainGSR

Thank You,

CaptainGSR

I received the airlift last week.
I am ordering parts for the job : coolant temperature sensor, intake manifold gaskets, throttle body gasket, one quart of coolant (planning on reusing the old coolant...)
Should I replace anything else while in there? The car only has 107000km (67000miles).

k722070

I changed the plugs and air filters listed as no later than every 4yrs.
not much else to do if the coolant system isn't leaking in the V or the glued distributor fitting is fine.

CaptainGSR

I replaced the sensor last week. I used the above advice and the Pelican article as a rough guide.

Here is what I have learned from it (it only applies to the DFI 4.8l V8 engines):

1- Leave the throttle body attached to the intake manifold. No need to separate the two.

2- To drain the coolant: I elected to replace my lower radiator hose (my choice). This allowed me to cut a small hole into the old one, therefore creating a small controlled leak, and avoiding a much predictable mess!
I built a funnel out of some 3.5" construction PVC pipes. Only about 5 liters of coolant came out of the bottom of the radiator. Another 1/4 of a liter came out of the temperature sensor hole when I unscrewed it.

3- Disconnecting the lower radiator hose from the radiator is a major PITA! Plan on over an hour of constant swearing and struggling. You need a small pry bar and lots of patience. It would be easy to damage the radiator, if you got carried away. Simply pulling on it after removing the metal clip is not enough! It takes time and plenty of back and forth motion. I used a thin block of wood to distribute the pressure from the pry bar. I made sure to put some silicon paste on the o-ring of the new hose.

4- Using the airlift: it keeps sucking new coolant until the reservoir is overfilled. You then need to use a turkey blaster to remove just under a quart of excess coolant from the tank.
I reused the old coolant + one quart of new coolant mixed with one quart of demineralized water = about 6 liters total. Then, I ended up having to remove about 0.75l from the system, to reach the "MIN" level.

5- There is a small vacuum line that plugs into the back of the intake manifold. I lost a small right angle connector and had to make a trip to the dealer...

6- The old intake seals were a bit dried up on my 2008. Replacing them was a good thing. Be careful when reinstalling the intake manifold. I can see how easy it would be to inadvertently pinch or drop one!

7- Extreme care should be taken with all the plastic connectors...

8- I applied some Silicone paste to all the o-rings (I used DC111), and a light coat of fresh motor oil on all the seals in direct contact with the engine block (personal preference).

9- The whole thing took me 2 days.

10- No need to depressurize/disconnect fuel lines on the DFI engines. :-)

11- Here are the torque values and sockets I used:
Coolant Temperature Sensor: 22 ft.lbs (I used a very deep 22mm O2 sensor socket)
Engine Torque Brace: 44 ft.lbs
Intake Manifold: I had to use a long T40 socket (my short 1/2" T40 socket with an extension did not fit) loosen from outside to middle (alternating sides), tighten from middle to outside in two passes (7.5 then 11 ft.lbs)

12- I also had to remove that black plastic wire cover to find the sensor. The two piece cover is held in place by two small vertical E10 or E12 screws (can't remember their exact size, but hard to reach, in the back, of course). You'll also have to cut and replace a long zip tie to remove the main rubber cable cover.
The temp sensor screws vertically into the rear coolant manifold. It would be extremely hard to access it without taking everything apart.
Here is a picture of its location with everything back together, except the plastic covers that go all the way around the top of the engine compartment.

touareg

Has anyone had success in doing this without removing the intake?

Just got a quote of 1200 dollars to change a $30 sensor.

Rossi

Looks like I s see m about to tackle my coolant sensor as I have the typical symptoms listed above.

On 957 4.8L GTS, how much coolant comes out? I am hoping just to swap it out and top it off, kind is the same way I did when replacing thermostat. Anyone can confirm? Thank you

Rossi

Tackled the job today. No need to drain the coolant if not due. I just removed all the coolant from the reservoir and when I removed the sensor, I truly lost just few drops. Hope this helps the next guy.

touareg

Thanks, I still have to do mine ...