What are the chances?
 

So I recently within the last 130 miles of my 130k miles on the car had a radiator replaced due to a pinhole leak causing my OCD to make it right and not stain my garage floor...I also had a transmission upgraded Valve Body installed and honestly, everything has been driving and feeling amazing! Until this last Sunday when I decided to drive a 12 mile loop and drive it hard in 40 degree F weather...nothing weird about it...at around 9 miles into the trip I get an annoying chime I have not yet heard from this Audi...Overheating Coolant! WTH?! So I slowed down, turned off all the amenities like stereo, seat heaters, etc...knowing that wouldn't aid much but eliminate any out of bounds focus...I cranked the defroster on HI along with the temperature and noticed the "heater" was blowing cold air...so I figured it must have been a faulty thermostat...well, I get home and let it cool and popped the hood...I saw the coolant (what was left) boiling feverishly in the reservoir and within 2 min, it was all over my garage floor...Oh great!

Long story long, I towed it back to the shop today and had them look it over with me acting like a parrot...all hoses looked good, all connections, sensors, etc looked as they should...I we then started it up with water in the reservoir, and popped the TB cover on the lefthand side of the engine bay to notice the water pump pulley was seized...I have read stories of issues like this occurring on vehicles but never on a 40v! There was a TB job done with a water pump, etc at a Seattle dealership at 98k miles in 2012...I have 30k miles on this "new work" and come to another failure...how common is this and WHY must everything happen to this thing at once...I hope the tranny doesn't capitulate and follow suit! Might be trading it in for a Corolla at that point!

Also, when observing the failures I incurred, I noticed a green sensor on the lefthand side engine near the 3rd intake runner bank...the housing is cracked...what is this and is it "worth" fixing or could it be "okay?"
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Another shop visit
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Sensor on right-side of engine bay on 3rd bank...green
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cracked sensor connection

Knock sensor connector
 

Mine are crumbling to nothing. I put some dielectric grease in them and they've been fine for 5000 miles. Sorry about the WP. Thats total BS. I just had mine done with the Blau parts kit- I used a dealer supplied thermostat though because I've heard aftermarket ones tend to fail.

Excellent! Thanks for the clarification on the sensor! Hmmm, I'll try your way and see if they hold up...no codes, but once things start to go, one needs to get them replaced or repaired unless you want a money vacuum...regardless, I'll get these sorted.

Thanks on the WP...crap-deal for sure but I'm getting OE parts all replaced with OE parts now and getting a PS return line from the rack to the cooler swapped too...do it now or never do it and get a different car kind-of deal...

My green connector is also cracked on one side, even started coming apart. I made sure the connections themselves were good, taped it up, and have had no issues for over a year.

Car is back: new timing belt, water pump, thermostat, tensioners, pulleys, replaced a leaking power-steering return line from the rack to the cooler and...had replaced a broken torque mount...sheesh! Anything more and I'll have myself a near $20k car...Thus far, she's driving beautifully and several noises disappeared, but other creaks have replaced them on the interior...drives me nuts but things I feel I can correct when locations are discovered. Nonetheless, I'm happy with it again!

Next thing Id like to do is modify the exhaust a bit to free up some intoxicating v8 sounds...will most likely start with an X-pipe, 2.5" all the way through to a resonator and muffler...if not what I'm hoping for, will modify to make better...so that being said, would you all recommend removing cats or putting in new cats, or, just leaving them alone? I do not have emissions to worry about where I live but sometimes, it's not a bad idea...what do you advise?

-Lieb

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