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I changed my cts today. It probably took 30 minutes and involved me breaking one clip so thanks for the tip to save the old one! I reckon about 3-400ml of coolant drained when I took the plug out. The old O-ring didn't come away with the plug but retrieving it was nothing at all.
The only thing I couldn't be certain of was that I'd seated it properly. It felt right, the clip went on but there's no reassuring 'click' like you'd get with other components. I did get 2 codes; p0118 and p2181, which I looked up and hope will clear after I've done a few miles.
Thanks again for the above guide, it is incredibly helpful.
I changed my cts today. It probably took 30 minutes and involved me breaking one clip so thanks for the tip to save the old one! I reckon about 3-400ml of coolant drained when I took the plug out. The old O-ring didn't come away with the plug but retrieving it was nothing at all.
The only thing I couldn't be certain of was that I'd seated it properly. It felt right, the clip went on but there's no reassuring 'click' like you'd get with other components. I did get 2 codes; p0118 and p2181, which I looked up and hope will clear after I've done a few miles.
Thanks again for the above guide, it is incredibly helpful.
how did it go? I have a p0118..gonna order the cts..just wondering if it's easier on the ramps as this is my first dyi job.
If you're getting a P2181 code its possible you need to replace your CTS. It seems like these things go bad all the time. Here's a cheap and easy DIY:
DIY for B7 Audi A4 2.0T FWD Coolant Temperature Sensor (CTS)
Here’s what you need:
Part # 06A919501A – Coolant Temp Sensor (GREY 2 pin)
Part # N90316802 – O ring
Part # 032121142 – plastic retaining clip
Flat head screw driver
Flashlight
Mirror
Step 1: Wait until the engine is very cold. You’ll be working behind the engine block near the cat and it gets pretty hot. Remove Engine Cover.
Step 3: Insert a flathead screwdriver into the small opening (indicated by the arrow above) on the electrical connector and gently pry up. Remove electrical connector and move it out of your way.
Step 4: Insert a flathead screwdriver into the small opening (indicated by the arrow above) under the plastic retaining clip and gently pry up. Remove plastic clip and try not to drop it. You may need it as back up later.
Step 5: Gently pull out the old CTS. Some coolant will come out but not too much. Locate and set aside the old O-ring on the top of the sensor. If you can’t see it, it’s up inside the plastic pipe where the CTS sits. Reach in there and pull it out. You may need it as back up later.
Step 6: Place new O-ring on top side of the new CTS and insert electrical connector into new CTS. Firmly push new CTS into the plastic pipe where the coolant came out. You do this pretty much blind so you have to feel around and make sure the new CTS is seated correctly.
Step 7: Place new plastic retaining clip into clip grooves until it clicks into place. This is somewhat difficult and frustrating because you have to keep the CTS seated correctly while orienting the clip to click into place in the grooves. You do all of this blind. It took me about 20 minutes to finally get it. If you drop the new O-ring or new plastic clip in the process, it’s possible it will be tough to find or retrieve from behind the engine block. Obviously you can use the old ones if this happens.
That’s it!
Thanks for the photos and the explanation! I've tried putting the CTS back in but I'm having trouble.. is the clip supposed to go behind the rubber O-ring? Because when I put it in it doesn't seem to stay in so maybe I'm not pushing it in all the way? Now that I took it out I'm afraid of taking to any shop and idk of any mechanics that can come out to me smh.
Thanks for the photos and the explanation! I've tried putting the CTS back in but I'm having trouble.. is the clip supposed to go behind the rubber O-ring? Because when I put it in it doesn't seem to stay in so maybe I'm not pushing it in all the way? Now that I took it out I'm afraid of taking to any shop and idk of any mechanics that can come out to me smh.
Hard for me to remember all the details as this DIY was about 6-7 years ago, but as I recall:
- it did take me some time to figure out the positioning and location for the O-ring and clip. So, as I found with a lot of Audi DIYs, just takes some patience and perserverence.
- The clip doesn't provide you a satisfying "click" when put back into place. It should fit snugly in the provided "groove", but it won't click or lock into place as is with other components (I believe).
- The clip breaks easily so, unless you have the original or a spare, be careful. If possible, look at the CTS itself, then the groove, then the clip and try to see how they might "best" fit together and snugly. People have mentioned on here that putting the car on ramps and going from underneath might be easier.
- I think the O-ring placement should be fairly evident, should fit inside the opening somehow. Again, have some patience with it. I believe the O-ring is there to provide a better "seating" for the CTS and to prevent some leaks. I'm thinking it should probably "behind" the clip.
- Don't stress too much. Get things back installed as best you can and check under your car for a couple days. No leak - you're good. Leak - try to seat the O-ring/clip again if you can. I don't think you're going to massively ruin the car if this isn't perfectly in place, is all I'm saying.
Just did it. Went through 2 clips. Came out easy. O-ring did not come out so just fished it out with my finger. Toughest part is getting that sensor seated flush and the clip on. I had to come over top pushing the sensor in with my right hand and with the left hand trying to slip the clip on. It's frustrating cause your not sure if the sensor is flush or "****-eyed". Several times after getting it in and starting it up it leaked quite badly. Pretty sure the top part of clip seated on 1 side of the sensor and the bottom of the clip slipped on the other side of the sensor. Pulled the clip back out and tried again. I found I couldn't push very hard to seat it though because of the angle of hand and was wondering if it just wasn't being pushed in far enough so the clip could pass through. I grabbed a 6 point 18mm socket with a short extension. Slid the sensor in and that made it a lil easier to handle the angle and push a little bit more pressure. When it finally did go on it just seemed to go almost effortlessly. So I guess take your time and wiggle the sensor around to find the right angle. It's all by feel. One other tip. The clip only goes in from the side. I would put the clip in 1st just so it would line up. The withdraw it just enough to put the sensor in and then slide the clip in again
01-11-2017, 01:32 PM
