overheating?
09-12-2014, 12:09 AM
#16
Instructor
if you read the temperature on a scantool it says lower then it does on the instrument cluster but still i assure you that the one that has the alu pipes done never goes past the middle mark. I know some cars let the water get hotter than 90 degrees but i don't count ours as one of them. If you turn on your ac it also gets to 210?
09-12-2014, 02:28 AM
#19
Worn water pump impeller can contribute to these "higher temp" indications.
When the A/C is turned on it masks the temp fluctuation as the fans turn on and supply additional cooling which in turn brings the temps down.
The water pump is a wear item and should be considered for replacement at 60,000 miles as part of preventative maintenance philosophy.
When the A/C is turned on it masks the temp fluctuation as the fans turn on and supply additional cooling which in turn brings the temps down.
The water pump is a wear item and should be considered for replacement at 60,000 miles as part of preventative maintenance philosophy.
09-12-2014, 02:35 AM
#20
Instructor
Well that seems like a good idea, i'm going to order the alu pipes and i'll order waterpump as well. Is this the right one?
http://www.ebay.com/itm/Audi-VW-Pors...b1a72b&vxp=mtr
http://www.ebay.com/itm/Audi-VW-Pors...b1a72b&vxp=mtr
09-12-2014, 03:09 AM
#22
Instructor
09-12-2014, 11:21 AM
#23
Three Wheelin'
The temp fluctuation is normal if you don't have the AC or HVAC unit on at all. The fans will shut off and they'll only kick on around 200 degrees. The thermostat isn't fully open until 210 degrees, so knowing these two things, you'll understand why the engine temp fluctuates like that in traffic without the HVAC unit on.
Once you turn the HVAC unit on, the temps *should* stay right around 180 unless it's extremely hot outside. If you don't have cold air coming out of the vents with the AC on, you might have one of two problems.
Not enough refrigerant in the AC system means the compressor won't even kick on, and the fans won't start spinning. There needs to be a minimum pressure in the AC system for it to even engage.
The other issue is you fans (or one of them) are not spinning when they should be, and you're not getting enough airflow at idle when you're stopped.
If it's warm out, and you turn the AC on, pop the hood to check that both fans are spinning. If they are, you still might have an AC issue, but your temps *should* be pretty solid.
As bigbuzuki stated, the other issue could be with the water pump. No real way to test for that except to pull it and look at the fins.
Once you turn the HVAC unit on, the temps *should* stay right around 180 unless it's extremely hot outside. If you don't have cold air coming out of the vents with the AC on, you might have one of two problems.
Not enough refrigerant in the AC system means the compressor won't even kick on, and the fans won't start spinning. There needs to be a minimum pressure in the AC system for it to even engage.
The other issue is you fans (or one of them) are not spinning when they should be, and you're not getting enough airflow at idle when you're stopped.
If it's warm out, and you turn the AC on, pop the hood to check that both fans are spinning. If they are, you still might have an AC issue, but your temps *should* be pretty solid.
As bigbuzuki stated, the other issue could be with the water pump. No real way to test for that except to pull it and look at the fins.
12-14-2014, 06:37 PM
#24
Instructor
I have 2 CS's. One goes from 180-190 degrees and the other one when ac is off fluctuates from 180 to 210. When filling ac gas i accendentilly overfilled so the ac did nopt come on anymore and the car stayed at 180 now that i gas the gas presure correct the ac come on normally but the temperature reaches 210 again. I'm confused. Outside temperature is hot. When driving temperature seems to be normal.
12-15-2014, 02:31 AM
#25
I rember when I first got my 04 CTT the temp NEVER EVER EVER went past 180. EVER! I noticed as the mileage went up I started to get a lot of the same symptoms as some.of the other posters. The Cayenne has a VERY well designed cooling system and a shi*.ton of frontal area. I noticed that the fans were not running after I shut the vehicle down the same as they usually were. Im convinced that the Fan Controller is to blame and that they go out slowly and erraticly like many electronics. The controller is included with one of the fans so no need to replace both.
One thing to keep in mind with cooling systems is that if coolant is not flowwing over the sensor, your not going to get a correct reading. On the Cayenne the temp sent to the guage is calculated by the dme. It's not exactly coming directly from the sensor.
Imagine this: your driving down the road and notice a sweet smell, is that coolant? Hmm, temp seems a little hot..... You pull over and see that your dripping and have lost all your coolant.
Guess what? The last reading that showed on your guage is the last correct reading before you dumped all your coolant and it stopped flowing over the guage. At this point radiant heat inside the coolant passages and steam are enough to keep the sensor around the same temp as when coolant stopped flowing over it.
At this point the damage is done and there is no telling how hot your engine actually got before you realized there was a problem and stopped the engine.
Food for thought for those contemplating the coolant pipe upgrades and dont forget about the two plastic tees that go behind the drivers cyl head.
Overheated engines are never right again. Especially all alum ones.
One thing to keep in mind with cooling systems is that if coolant is not flowwing over the sensor, your not going to get a correct reading. On the Cayenne the temp sent to the guage is calculated by the dme. It's not exactly coming directly from the sensor.
Imagine this: your driving down the road and notice a sweet smell, is that coolant? Hmm, temp seems a little hot..... You pull over and see that your dripping and have lost all your coolant.
Guess what? The last reading that showed on your guage is the last correct reading before you dumped all your coolant and it stopped flowing over the guage. At this point radiant heat inside the coolant passages and steam are enough to keep the sensor around the same temp as when coolant stopped flowing over it.
At this point the damage is done and there is no telling how hot your engine actually got before you realized there was a problem and stopped the engine.
Food for thought for those contemplating the coolant pipe upgrades and dont forget about the two plastic tees that go behind the drivers cyl head.
Overheated engines are never right again. Especially all alum ones.
01-30-2015, 03:48 AM
#27
01-30-2015, 03:52 AM
#28
I rember when I first got my 04 CTT the temp NEVER EVER EVER went past 180. EVER! I noticed as the mileage went up I started to get a lot of the same symptoms as some.of the other posters. The Cayenne has a VERY well designed cooling system and a shi*.ton of frontal area. I noticed that the fans were not running after I shut the vehicle down the same as they usually were. Im convinced that the Fan Controller is to blame and that they go out slowly and erraticly like many electronics. The controller is included with one of the fans so no need to replace both.
One thing to keep in mind with cooling systems is that if coolant is not flowwing over the sensor, your not going to get a correct reading. On the Cayenne the temp sent to the guage is calculated by the dme. It's not exactly coming directly from the sensor.
Imagine this: your driving down the road and notice a sweet smell, is that coolant? Hmm, temp seems a little hot..... You pull over and see that your dripping and have lost all your coolant.
Guess what? The last reading that showed on your guage is the last correct reading before you dumped all your coolant and it stopped flowing over the guage. At this point radiant heat inside the coolant passages and steam are enough to keep the sensor around the same temp as when coolant stopped flowing over it.
At this point the damage is done and there is no telling how hot your engine actually got before you realized there was a problem and stopped the engine.
Food for thought for those contemplating the coolant pipe upgrades and dont forget about the two plastic tees that go behind the drivers cyl head.
Overheated engines are never right again. Especially all alum ones.
One thing to keep in mind with cooling systems is that if coolant is not flowwing over the sensor, your not going to get a correct reading. On the Cayenne the temp sent to the guage is calculated by the dme. It's not exactly coming directly from the sensor.
Imagine this: your driving down the road and notice a sweet smell, is that coolant? Hmm, temp seems a little hot..... You pull over and see that your dripping and have lost all your coolant.
Guess what? The last reading that showed on your guage is the last correct reading before you dumped all your coolant and it stopped flowing over the guage. At this point radiant heat inside the coolant passages and steam are enough to keep the sensor around the same temp as when coolant stopped flowing over it.
At this point the damage is done and there is no telling how hot your engine actually got before you realized there was a problem and stopped the engine.
Food for thought for those contemplating the coolant pipe upgrades and dont forget about the two plastic tees that go behind the drivers cyl head.
Overheated engines are never right again. Especially all alum ones.
01-30-2015, 12:17 PM
#29
Instructor
01-31-2015, 09:30 PM
#30
The expansion tank simply allows excess coolant to escape the system with heat buildup and draw it back in as it cools.