Intermittent Fan problem

[SWFLHOMES]

I have seen different parts of this topic but none that addressed an intermittent problem. I have been having A/C and coolant temperature problems for a while now. Both the dealer and very reputable Indy A/C shop cannot seem to find out what is going on. My fans work but after much research I am convinced that they are not going on when needed. My temp is going over the typical 180 mark by about 30 to 40 degrees when at idle. If I do not turn the econ button on when at idle and the temp rises (occasionally) I will get freon blow off at the compressor. Would I be wrong to start checking the coolant temperature sensors or any other fan sensors. I found a thread on the boxter that jumps the relay but it seems the cayenne does not have the same relay set up.

Coolant is good and full

I installed a new coolant reservoir tank (per the dealers recommendation)

Coolant pipes done 2 -3 years ago

New water pump

Thanks,

Craig

[deilenberger]

Certainly be worth checking the temperature sensors - if you can get at them. One of them is located on the cast cooling manifold at the rear of the engine, and looks to be a bear to get to - probably requiring intake manifold removal..

[wvicary]

There is also a control module for the cooling fans. The dealer couldn't find any faults? The coolant temp sensor has an updated part number.

[SWFLHOMES]

The dealer could not find any faults and said they were able to operate the fans. I know it's running hotter than normal and I can see the temp rise when I know the fans SHOULD be kicking on that's why I think I should trace down what is or isn't triggering the fans but more important the high speed fan.

[working4it]

The dealer could not find any faults and said they were able to operate the fans. I know it's running hotter than normal and I can see the temp rise when I know the fans SHOULD be kicking on that's why I think I should trace down what is or isn't triggering the fans but more important the high speed fan.

Any updates...?

[SWFLHOMES]

I was hoping someone could send me the a diagram location of the coolant temp sensors, and or sensors for the fans.

Edited September 13, 2011 by SWFLHOMES

[working4it]

I was hoping someone could send me the a diagram location of the coolant temp sensors, and or sensors for the fans.

Here you go...hope this helps

Cooling Sensor.pdf

Thanks Loren for changing it to a .pdf!

Edited September 13, 2011 by working4it
Change doc file to PDF

[SWFLHOMES]

Thanks for the PDF! I will replace it this weekend and see what happens. I guess there is only 1?

[wvicary]

There is only the one that I know of. I would recommend replacing the sealing O-ring for the sensor and the plastic retaining clip. Often the clip breaks on removal or falls into the abyss at the rear of the engine so it's wise to have a spare at hand.

[working4it]

Any update? Has it been resolved?

[SWFLHOMES]

I had an indy shop replace the a/c fill valve with a new brass one. I had 1 more freon blow off right after that but nothing since. I don't know if the fill valve replacement worked or if the fan just fixed itself. I no longer have an A/C or fan/temperature problem?

[SWFLHOMES]

Just a quick update. I replaced the switch and it solved my a/c and fan issues. It seems that my condensor fan was coming on intermittently and causing the a/c to build pressure and blow off freon. The job is not difficult if you have done the coolant pipe replacement. You have to remove most of the same parts. One HUGE help was that I had a 22 mm O2 sensor remover (it attaches to the end of the ratchet). It fit right over the sensor after the connector was removed. Prepare for some coolant to come out so be ready to plug it with a finger or have the new sensor ready.

[wvicary]

So it was the coolant temp sensor, good result.