Cadillac CTS First Generation Forum - 2003 - 2007 Discussion, 2003 CTS thermostat in Cadillac CTS Coupe, Sport Sedan and Sport Wagon Forums; http://www.cadillacforums.com/forums...ing-chain.html
Check out that thread, it may help....
Ii got mine done cash deal with a cadi mechanic who i know. i asked what he wanted for it after he was done and was expecting 2-300...he only wanted $50
Sounds like the kind of mechanic I've been looking for, any chance of a reference? I live in the GTA and need hella work done to my old girl. Not expecting crazy prices like that but I got a lot of work to do and if he's good and reasonable, I'd like to get in contact with him. The Caddy dealership in my city is a joke, won't take my car there anymore but I'd rather an experienced caddy tech than my regular guy.
When replacing the thermostat on the 3.2L, make sure the t-stat housing gasket is the correct size. The first one I got had a housing gasket more like an o-ring and allowed a ton of coolant to leak. The gaskets are not sold alone; you'll have to buy the entire housing again, or along with another t-stat. It was a pain but got it done. I didn't even remove the fuel lines, just turned them to the right side of the engine. the lower manifold was a little tight, but came out; you'll have to give it a little tug from one side or the other. It took me a while because I had trouble removing the t-stat housing from the coolant tube that runs behind the timing belt to the rad hose.
My mechanic replaced my Thermostat and front brake job "Pads&Rotors including brake lines which I ignored the recall like a jackass and one of the brake lines broke lol all said and done parts and labor $463 not bad I am happy no more check engine light. Word to the wise what my good friend "Mechanic Mike" told me never ignore a recall especially when it comes to your safety.
450 is a very reasonable price, the shop i work at usually charges 8-900 with parts and labor...alldata calls for 3.8 hours to do...i did mine and it took me 3 hours, and the guy talking about a sensor too, i really don't know what hes talking about but have yet to see one with a thermostat...just intake gaskets, thermostat, thermostat gaskets(don't forget the 2 o-rings on the split housing under the driver's side cams), and if your valve cover gaskets are leaking it'd be a good time to do them, since you're pretty much there.
I have replaced the Thermostat today; it is more or less 5 hour job. My dealer gave me $800 estimate just for thermostat. I asked for coolant temperature sensor too but he said it is not included.
Anyway I have done with my friend paid him some money.
Parts you need are following.
Complete Gas kit for the intake system, on rockauto.com acdelco is about $65. When you are opening the intake why not change all those.
Thermostat with hosing, I bought from GM dealer $65 since it is way buried in the engine and cannot risk cheaper brand. With gas kit.
Get o rings for the coolant hosing there are two O rings there it is dealer item $3 each.
Coolant temp sensor, the green one.
Taking out the sensor is little tricky when you get it loose, first take out the side hosing for that you need to open the side one screw for that hosing.
We also changed the gas kit for the oil cooler too which is also right there but it is optional.
I will post pictures. IMG_0647_1024.jpg
Now disconnect the fuel lines and then take out middle intake, also disconnect the injector connection. IMG_0652.jpg_1024.jpg
Now first take out the side hose. IMG_0655_1024.jpg
Now unscrew the thermostat and you need to wiggle it out trick like sofa when you try to get into 3rd floor and door is kind a small. IMG_065_10247.jpg
I replaced the thermostat on my euro-spec CTS about a week ago. I think there are really good posts about the assembly-disassembly procedure so I will not go again over that. I just wanted to point out some interesting things, especially for those who are reluctant at replacing the thermostat when the PCM starts to throw P0128.
Having read several threads about thermostat failure, I found that this was commonplace. I also read about blown cam cover gaskets and related oil loss and near-fire incidents due to PCV system blockage. And, with time, I came to think that the faulty thermostat could be a contributing factor in the blocked PCV and gasket blowout events.
My hypothesis goes as follows:
a) the thermostat starts to act up long before the PCM starts throwing any codes. But anyone having the instrument cluster without temperature gauge (with the infamous clock) will not get any clear hint of thermostat failure until the codes start to show up. I can bear testimony to that, because, at the sight of the gravity the above two issues, particularly the PCV blockage, I decided as a precautionary measure to upgrade my instrument cluster (was the one with the clock in it) to the later model which has the temperature gauge instead of the clock (it is plug-and-play swap, I can give the p/n's if anyone is interested in the swap). And sure enough, just short of 100.000 Km I started to notice that the temperature gauge needle, which usually stays solidly fixed in one position just under the middle of the dial, started to move to the left when going down a slope with the foot off the gas pedal, or even just when coasting if the temperature whas anywhere below 5ēC. The effect got progressively more pronounced and I also had the impression that the cabin heating was not what it used to be. Yet no codes showed up.
b) there is something weird with the original PCV system in those vehicles with the 3.2 engine. Clean air is aspirated from throttle body over some pipes which then disgorge into the crankcase, then dirty air (mixed with oil and water vapor from cylinder blowby) is in turn aspirated from crankcase and fed to the upper intake plenum through a nozzle (under a small junction box which is called the primary hose adapter, the one with the cadillac logo on it, see TSB 05-06-01-007a (PCV system upgrade) as well as pages 6-33, 6-204, 6-302 in the shop manual). This nozzle has got two sets of holes, the two 1 mm holes connect to the dirty air hose (with blowby sludge in it) and the two 4 mm holes connect to the tank vent canister (with gasoline vapours). The mentioned TSB calls, among other things, for enlargement of the two 1 mm holes up to 4 mm (same size as those connecting to the canister). Since you have to remove and disturb the PCV adapters and so on to replace the thermostat, I thought it was a good time to carry out this TSB 05-06-01-007a, for which I had bought the upgrade kit long since. And sure enough, the dirty air conduits in the primary hose adapter were filled with a kind of yellowish sludge (seemingly an emulsion of oil and water) I have seen mentioned in threads related with blown cam cover gaskets, PCV upgrade and the like. I enlarged the holes as per the TSB and then had a hell of a job to clean all that sludge out.
c) in my view there is a link between failed or poorly performing thermostat, shortcomings / faults in the original PCV system and plugged PCV system (the TSB says this may only happen in extremely cold temperatures). Firstly, I guess the original 1 mm holes are far too small for the blowby byproducts, which may solidifiy in a creamy emulsion and even freeze due to their water contents, even in relatively low-mileage engines (perharps an inadvertent reversal in hole size spec between dirty blowby air / canister vapour conduits occurred when designing the hose adapter). Secondly, the original clean air conduits go through this same adapter, and so are thermally coupled with dirty air conduits, performing a cooling effect on the blow-by gases and promoting the formation of creamy emulsion (this is one of the things the TSB addresses, by separating the clean air and dirty air conduits). And thirdly, if the thermostat is faulty, the engine will be running at temperatures oscillating below the intended setpoint, long before any codes are thrown. This, which is exacerbated at low ambient temperatures, may contribute to the PCV system getting frozen.
So I would advise anyone having the P0128 code to look carefully into the issue in order to avoid greater evils. Bear in mind that P0128 may have other causes besides faulty thermostat such as for example coolant bypass valve inoperative or having unplugged or loose vacuum command line. And I would also reccomend to perform the PCV upgrade TSB, there is really a sound reason for it and it may avoid dangerous breakdowns and costly repairs.
Some pieces of advice to those replacing the thermostat: the screws attaching thermostat housing to engine block disgorge into water jacket and therefore need to be coated with thread sealant (shop manual page 6-273 says GM P/N 12346004, canadian P/N 10953480 but I used LOCTITE 572 both on the thread and around screw holes on thermostat housing, upper and lower side, being careful not to stain the rubber seal with it). Also, replacement of the o-rings of the water outlet pipe is extremely important. Since they are difficult to access, replace the inner one first, and then the outer one, leaving the original outer one in place to allow sliding the new inner over the new outer and damaging it. Anyone doing the repair in Europe can get these o-rings (and many other engine parts) at any OPEL dealer, p/n is 9129999 and they come in kits of 2. This is because the 3.2 engine in the CTS shares a majority of parts with the Y32SE used in the OPEL OMEGA.
Also clean the water pipe from oxydes and deposits with sand paper at the coupling with radiator hose to avoid leaks.