Coolant Temp Sensor location 3.0

[newvances]

For the life of me, I cannot find the Coolant Temp Sensor (the one on the radiator. Not the ECT) on a 02 3.0 Avant. I've used the search tool to no avail. Can someone guide me to the right direction?

[DEPECHE]

#35 or #45, One is a sensor and the other is a plug. Not sure which one is actually the sensor.

[DEPECHE]

...What?

That's not even a 3.0 engine...

There are two CTS's? I thought it was just one at the back of the motor that people commonly replace with the updated/revised green-top?

That is a 3.0 6 cylinder engine.

Yes, there are 2 sensors, one is more prone to failure. #3 is the GREEN sensor most people replace, the BLACK sensor is either at position 45 or 35, one is a sensor and the other is a drain plug.

[john_gonzo]

More pics here

DIY-3-0-G62-Green-coolant-temperature-sensor

[newvances]

Your picture does not have a 3.0 engine. It has the 3.0L V6 TurboDiesel offered in Europe on cars like the A5, which is very different. What OP is looking for is for the NA-market, naturally-aspirated V6 3.0 aluminum block w/ iron liners. I assume this matters.

I believe "ASN" is the engine code for the 02' 3.0, and here is the "Coolant System" diagram I found on ETKA for that engine. I assume it applies to all of the 3.0's, whether they be ASN, AVK, and so on.




#4/5 is the drain plug.

According to ECS Tuning, there is only one CTS, and that is the one behind the engine that people replace with the updated green-top.



OP's location is Tennesee, so I assume he has the NA 3.0 and not a turbodiesel european 3.0 that came out after the B6 stopped being made.

That is correct. It is it the 3.0 non tdi. I'm looking for the Grey or the sensor at the radiator. I see on the diagram that #45 is a drain plug and no sensor.

[87supraman]

My 02 3.0 has no sensor there either. Just a plug.

[newvances]

#35 or #45, One is a sensor and the other is a plug. Not sure which one is actually the sensor.

This is what I was referencing.

[newvances]

So where is the sensor on the v6 3.0?

[87supraman]

CTS is located behind the passenger side head between the firewall and engine. Green sensor is the only one on the 3.0 avk.

[newvances]

Thanks for the clarification. Its odd that ECS Tuning and other part stores list the "grey" 2 pin sensor (lower radiator hose) for along with the green 4 pin sensor (ETC) as parts for the 3.0

[SJorge3442]

Thanks for the clarification. Its odd that ECS Tuning and other part stores list the "grey" 2 pin sensor (lower radiator hose) for along with the green 4 pin sensor (ETC) as parts for the 3.0

That is strange. We have the one green one, and then a low coolant sensor in the coolant tank. Thats it. What is wrong with your car that you are changing these sensors?

[newvances]

That is strange. We have the one green one, and then a low coolant sensor in the coolant tank. Thats it. What is wrong with your car that you are changing these sensors?

My fans are running on high while the car is running and they continue to run for up to 5 min after the car is turned off. This is causing battery drain. I checked the relays and they look brand new. Relay box is bone dry. Temp gauge is reading normal. Heater is blowing hot as expected. I was going to change temp sensors before I spent the money on the Fan control module. VCDS shows no codes. I'm open to suggestions.

[SlickFix]

I happen to have one of those grey sensors from ECS Tuning, as I decided to replace them both as preventative maintenance...only to discover that my 2003 3.0 AVK does not have the grey sensor. It just has a plug on the bottom.

[imnuts]

My fans are running on high while the car is running and they continue to run for up to 5 min after the car is turned off. This is causing battery drain. I checked the relays and they look brand new. Relay box is bone dry. Temp gauge is reading normal. Heater is blowing hot as expected. I was going to change temp sensors before I spent the money on the Fan control module. VCDS shows no codes. I'm open to suggestions.

I don't know where exactly, but there is a way to read the temperature reported by the sensor via VCDS. It has two thermocouples in it, one goes to the cluster, the other to the ECU, so the cluster can have the proper temp, and the ECU can get a different reading. That would be the only way to really confirm the sensor is bad. Given the low cost though, you're only really saving yourself the aggravation of changing it out. I hope that it the sensor will fix it for you though.

[newvances]

Thanks for the feedback. I have started the removal of the hoses, and the plate to get to the sensor. Unfortunately, the crankcase vent hose crumbled in my hands and now I have to replace it too....

[SJorge3442]

Thanks for the feedback. I have started the removal of the hoses, and the plate to get to the sensor. Unfortunately, the crankcase vent hose crumbled in my hands and now I have to replace it too....

You can replace this whole system with the appropriate sized heater hose and brass fittings from Lowe's!! Save your money and spend it else where. those replacement kits are super expensive. Find the user JohnGonzo on here and check his pictures. He's done this sucessfuly.

[john_gonzo]

You can replace this whole system with the appropriate sized heater hose and brass fittings from Lowe's!! Save your money and spend it else where. those replacement kits are super expensive. Find the user JohnGonzo on here and check his pictures. He's done this successfully.

You said it!

I used heater hose with 3/4" internal diameter. The extra elbow mentioned in the first pic is visible in the second and third pictures.







My PVC tubes had this yellow slime inside.


The same slime was thick inside the valve covers. The covers have baffles that can be pried out for cleaning.