Good day all, I've recently purchased a 2000 STS 77k. My first Cadillac though I've rented many in the past (had free upgrades at Enterprise). I'm very happy with my purchase, it's a solid used car and a great ride.

I'd read through many of the Seville and Northstar threads before I'd purchased to be at least as well informed as I could about the Car. I first off want to thank all those who contribute that helped me, I rarely need to post for my questions are often already asked and answered. I'm sure as time goes by I'll have a few and do so perhpas these will help others in the future also.

I'd read thru all the codes before purchase (or testdrive) then after..
Some network stuff in the history. 1,000 miles since and there is nothing new in the codes so... we'll see.
I will mention 'Change Brake pads' which I know are the sensors, he replaced rotors and pads but not the senors so not too much there which seems good, car stops well and doesn't pull.
I ran a couple WOTs and all seems well.
I've done some highway driving (~500mi) and tested steering and shake at various speeds 55-65 / 65-70 / 70-75 etc.
No top speed runs yet till I fully go over the car.

I've purchased all new DexCool and am picking up the tablets to renew the coolant. I'll drain and refill the Oil and Filter as to know for sure when/what's installed. (seems the shops around here don't stock the tablets!)

I'll do some of the work but other I'll take to the shop, which leads me to my first posting question:

The AC was iffy when I bought it, I knew this and was willing (even at shop cost) to get it repaired or corrected. For a 5 year old car 77k mi I'd just as soon do this now and know I'm good for the next 5+ (I hope to keep this for awhile).
I've noticed a tapping sound that ONLY occurs when I have the HVAC system turned on and goes away when off. I don't believe this to be the injectors or carbon knock since I can make it happen at will. The dealer will look it over on Monday but I thought it'd be nice to have some input from the local residents here.
My thoughts are the compressor bearing or clutch? Possible the extra load on the belt maybe the idler pulley? OR maybe I'm just nuts ! It's deffinatly tapping and not squealing. I haven't looked too closely because regardless of the noise, the AC isn't cold and I won't work on this area of the car, hence the dealer visit (also to get a fob/key programmed as well).

So there it is, I look forward to my visits here to keep abreast of changes and information shared. I've used 'other' forums as well for previous cars and these are great resources for the 'DoItYOurSelfer'... Thanks Jack

btw my future posts will be shorter :2thumbs:

Welcome aboard! You'll find this place to be incredibly helpful, or just some incredibly interesting reading if you've got some spare time. A half dozen or so of the folks on here are extremely skilled and will go into hugely detailed discussions, which are great fun, at least for me, to read, even if I don't have the problem being described. Good luck with the A/C and enjoy the car!

Welcome Jamdmyers:welcome: , I joined in March as well. I have had all of my questions answered as well. Like Spyder said, we do have some extremely skilled people here and they are very helpful.I hope you continue to have success with your new purchase(seeing as you made a very informed purchase).Good Luck with the AC.Try not to get any tickets :cop: while testing out the N*:) .

I dropped the car at the dealer today and discussed my symptoms with the Service Manager. The clicking I hear is the comressor engaging then disengaging. This is due to low pressure in the loop and will occur even if you don't get the coolant low pressure code for the hvac. He seemed to know this symptom well... I'll update next week when they find the root cause. jm