MY97 986 Water Temp
 

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?

anyone? :D

Does it stay past the "0" at hwy speeds or just in slow traffic?

No matter traffic or hwy, its still the same.

Well your first discription is alittle confusing but heres how it works, in hot weather (80+F) and even in 70F the temp gauge will sit on top of the 0 on 180. When the AC is off (meaning the snowflake is not lit on ac controls) the fans will turn on when the temp needle reaches the far side of the 0, until it drops to the near side of the 0 towards the 8.

With the AC on, the fans run 100% of the time and usually the temp needle will NOT go beyond the near side of the 0, unless you were racing the engine on the freeway for 10 minutes straight, then it'lll take some minutes of easy driving to drop back down to the near side of the 0 on the 180 mark.

The "0" of 180 is just an indication, acutally, I'm in HK and the temp guage is using Celcius, I just follow F. to explain. Anyway, somtime, the pointer goes beyong the 3rd mark.

After a normal drive and turn off the AC, the radiator fans are still on, I guess this is normal.


But the engine compartment fan is not always on. Even it turns on, the temp didn't drop much, let say only few degree drop and the coolant temp was 103C ~107C, high enough?

Thanks for the explanation, CJ ! I have been wondering that for a long time. I noticed that the car runs considerably cooler with the AC on and I could not for the life of me figure out why :confused:

Nick

My 01S normal operating temp with AC on or OFF is in the middle of the 8 in 180. It almost never goes past the 8.

Well your fans probably didnt turn off that time when you off'ed the AC cause the temps were at the point of when the Car wants to trigger them, They will trigger and stay on till the temps drop about 3 degree's then the temp will gradually raise back up and then the fans will turn on again till the temp drops 3 degree's... its a never ending cycle.


The Engine compartment fan triggers at odd times, and usually for 5 minutes or less, unless its really hot then you'll hear it... Sometimes you think you might be hearing the engine compartment fan but it will be the Air-Injection pump for afew minutes. In otherwords, You'r fine.

I heard someone on another forum say that the Needle's arent too accurate when trying to read temps due to the fact that the temp needles might be alittle off center from another temp needle... especially true for someone whos installed aftermarket gauge-face overlays.

I usually don't pay atention to the needle too much because of the cycling of the radiator fans..

the only problem I had was the collant bottle slit down the seam, then I went through about 3 radiator caps to get one to hold the pressure indicated.. durring that whole time the car never overheated...

The big indicator I had was the coolant boiling over from the bottle..


my needle stays around the 180 mark....

if your temp is wandering farther than that, or the a/c high temp cut off activates, look for some problems. THe most common one I have seen is air in the system. the boxster has bleeders all over the car for getting air out of the cooling system, itz quite a pain sometimes...

With the AC on when it's really hot ( it's been in the 90's here this week ) the temp is right between the 8 and the 0. With the air off, the temp is right in the middle of the 0.

According to CJ's explanation, I assume this is normal ?

Thx for guys comments.

I just found something new, i just drove the car and alomost hot the RED mark, I shut off the A/C and turn on the heat, the temp drop very fast, I suspect the thermostat or water pump got some problem. BUT, the stange thing is, the car does not have the water leak from water pump, hoses, bleeder valve, since last inspection on early July. I will get the service shortly, when my mech. receive the throttle cable, will fix it at once. I will let my mech focus on the thermostat.

Interesting thing is, I go thru other threads, some talked about the "00" or "01" coolant tank cap. Although mine is showing "01", I still buy a new (honestly, its chaep, give a try ^_^). The part no. on the cap shows "02" , but Porsche dealer sill calls it "01". I will change the cap tonite and keep you guys post!!!

:)

After changing the new coolant tank cap and tested twice, the temp is acceptable, it's not passing the 3rd mark, its aroung "0" of 180.
But, 1 problem I found, white smoke!!! But it happend when the car just start after a night. I don't know, is it ocasionally happend in Boxster or common in Boxster.

Smoke on start up is pretty common
 

Especially is car has been driven hard and then parked. I often have a few seconds of smoke (blueish white) on start up. It does come and go however....Don't think it is anything to worry about unless there is ALOT!

So, I ignore about it until I can see alot ^_^

I would ignore the smoke unless it happens more than once every 6 months if your driving her gently.

Normally, I ignore what I saw when the car is running fine. I did the same on 951 to, although it has oil leak in turbine. But for flat 6, I'm new for that, so I should study more about the flat 6 egnine.