MY97 986 Water Temp

[djoa]

Hi folks! I go thru the forum and saw so many thread about the temp of 986. Me have the same issue of high temp.

Driving time under 30 mins with AC on, it seems to be normal, the temp point to "0" of 180. Outside temp is around 89F. Its acceptable for me, since the AC still on under this condition.

Driving time over 30 or more with AC on, it seems wierd to me, the temp point over the "0" of 180 or even higher. Sometime, the AC shut off itself and back on. BUT, the warning light never turn on so far.

What I have done on it and observe:
- Coolant Temp sensor - no help
- Swap the relay of Engine Compartment Fan relay with Horn relay - no help. The fan is not on when I assume it will turn on in over the point "0" of 180. I guess the relays work because the horn still work after I swap those relays.
- Flush and new coolant - no help
- No water leak on carpet or gorund
- BOTH radiator fans turn on always (Of course, I turn the AC on)

My questions:
- It's relate to coolant tank cap? I saw the article in 996 about the cap, the pressure will leak using the old style cap. Is there any cap case leading to pressure leak in 986 as well?

- Anyone experience the same?

- The engine compartment fan only turn on in randomly pattern, I guess it's not logic because there is no reason the fan still OFF in high temperature. What do u guys think?