I was wonderering if anyone on here new where this is located. I checked out alldata.com and it gave me a drawing to show me where this was located but I just can't seem to find it. Even my younger bros auto tech class couldn't even find it. Its a pretty small piece. Thats what makes it so tough to find.

any input would be greatly appreciated.

 

Try this. I found this site for the same reason as you. Hope it helps.
Replacing the Engine Coolant Temperature Sensor (G62) Prior Experience: None Necessary
Cost: approx. $25.00
Time: aprrox. 25 minutes
After getting repeated DTC's regarding me engine coolant temperature sensor, I decided to replace the sensor. In particular I was getting the message: 16502 - Engine Coolatn Temp. Sensor (G62): Signal too High
P0118 - 002 - Lower Limit Exceeded - Intermittent Word on the street is that the ECT sensors go bad quite regularly on our cars, so I figured I would just pick on up and replace it. There are actually two coolant temp sensors on the B6 A4's. The one I replaced was the one giving the error - G62 NOTE: This should be done with a COOL engine! You will want to open the coolant reservoir lid to releave any pressre that the system may have, and then CLOSE it before removing the sesnor (this will prevent coolant from leaking out while you change the sensor) SUPPLIES - The only thing you need is a hex head bit and the speed sensor and a medium sized flathead screwdriver What $$ ECT Sensor, (G62) 25.00 Once again, one of the hardest parts about replacing the sensor is finding where it is located. The G62 ECT sensor is located at the back of the engine block - RIGHT against the firewall. This location is not ideal, espceially if you have big hands. It took me much longer than expected to replace the sensor since I struggled to just get a hold of it. The pic on the left shows the general location, and the pic on the right shows the location after I have already removed the electrical connection (which is a PAIN) The sensor itself is only held on by a small retaining clip. Although you will be able to see it when you look, it is impossible to get a picture of. I have included a picture of the clip once it is out though. It is shown to the left. The green circle shows where the coolant temp sensor WAS located. Inorder to get the clip off, I lightly pryed it off with the screwdriver by inserting the screwdriver where the red arrow points. You will know what I did once you see it. Once you remove the clip and the wiring harness, you can grab the sensor and pull it vertically. It will take some force to break it free because there is an O-ring holding it in place. If you have no pressure in the coolant system, and the lid is on the reservoir, then you should not get any coolant leaking. Install the new sensor in reverse.

 

I have an 2000 a4 2.8 and i'm wondering if that sensor is in the same spot in my car compared to the pics above? I've only had my car like 3 months so I haven't gotten a good look at the motor yet. Checked the code last night and got p1296. I cleared the CEL and i'm going to buy the sensor this weekend and try to replace it. Any help would be greatly appreciated. Thanks

 

On the 2.8 the sensor is near the back of the engine, kind of buried near the back of the passenger side cylinder bank. You have to take off the beauty covers from the engine to find it. It's inside the V of the engine though - root around down there and you'll likely see the green connector. There are other colors that were on some cars, but the green one is the most prevalent from what I've seen.