Check engine light was on, Autozone read it as coolant temperature too low, so I brought the car to a mechanic who only works on Volvo's. Have used him a few times in the past and he was reasonably priced and fair, IMHO.

Mechanic is telling me that starting in 2002, replacing the thermostat is more costly, because you can't just take off the housing and replace it. The thermostat is "embedded" in to the housing, so the part is over $150, plus you need to remove the steering pump, and all told, it will cost about $360 to do the job.

I told him to just do an oil change for now. Went to pick up the car and he charged me $90 for the oil change!!!!!!!

Starting to wonder if this guy is trying to take me for a ride. I am calling my local garage who works on all cars, plus Boston Volvo Village tomorrow for comparisons. I am seeing conflicting posts on a few forums, saying the "integrated" thermostat started in either 2002 or 2003.

Can anyone confirm how long it should take, and whether this year has the legacy style or newer (integrated into the housing) type?

Also, tempted to do it myself. Dealer says I should also replace the sensor. Is that just good practice, or can I do without replacing the sensor?

 

I looked at some diagrams for the 2002 XC and didn't see the integrated housing for that year. I think there are three issues here: 1) you'd need to test the ECT sensor (engine coolant temp ) to see if its in spec. A temp sensor is a simple bolt in change. 2) go to volvopartswarehouse.com to find the diagram and you will see the thermostat is embedded in a housing similar to older Volvos meaning there's a cap to the upper radiator hose with two screws mating to the housing, and the thermostat/gasket sits in between. The cap and housing are aluminum - meaning no wear out - just replacing the thermostat and gasket is done by removal of the cap 3) access to the cap and housing may be limited requiring some parts removal for access. You'd have to judge that by following the upper radiator hose to the cap to see if there's room to access for your model year. IMHO, you should change out both but my bet is on the temp sensor not the thermostat... A quick call to a dealer can also give you an estimate for effort/complexities. Note ECT sensors go for $20 aftermarket, $50 OEM so not an expensive add to the repair.

 

In my opinion, I'd suggest you take a step back and asses what you know and want before you draw any conclusions. You bring up two important and separate issues.


Your mechanic charged you $90 for an oil change but what oil did he use (mineral, synthetic, A5/B5 etc.), did he do anything else etc. Lets see if he is ripping you off or did he provide some value for money.


Next, Volvo did make a change to supply the thermostat housing as a complete unit rather than just what we traditionally know as a thermostat. So, your choice (if you can find the parts) is to replace what you think is wrong. Your mechanic (technician?) gave you the technically 'correct' answer so I would not blame him. If you want him to stand behind his work then he needs to use the parts as they were designed. As soon as he (or you for that matter) make your own decisions on which parts to replace then the responsibility becomes yours.


I'm not defending your mechanic or trying to dampen your spirits but just asking you to take a 'big picture' look at the situation before you strain a potentially viable relationship.


In addition, take a look on-line at the DTC. It probably says that the vehicle took too long to change temperature and that is where the thermostat-versus-ECT sensor challenge comes in. The ECM monitors the ECT voltage change and maps that against time. When the time to change voltage is too long then the DTC is set. From what you have written, that would be my interpretation as to why the confusion. Thermostat is easy to test and you can monitor voltage with a generic tester over time but the confusion might arise because there is not a known spec out there that everyone agrees on (that I know of). This is done because emissions are greater with a cold engine so they want to monitor the operation of the thermostat.


So, if your mechanical skills allow you to remove the thermostat and can find a like replacement then that becomes an option. Testing is fairly simple. Insert a piece of string into the thermostat (pry gently) and suspend it in water. Put a thermometer in the water. Heat the water and note the temperature at which the thermostat opens (it will fall off the string) and compare that to specification. Then you'll know if it works. Since it is a simple wax filled device it should be relatively easy to determine if it is good.

ECT is different as the resistance changes and that affects the voltage to the ECM. It could have a 'bad spot' where the signal to the ECM is wrong but that only happens at a certain temperature which you might miss if you don't watch it all the time.


My 2 cents for what it's worth. Let us know how you get on.

 

At this point, ideally, I may change it myself, and won't bother testing the existing stat or ect sensor, I will simply buy new ones, for the minimal relative cost.

The question now lies in whether I have the new "integrated" housing/stat, or if it is traditional style where I can pop in a new one and use the existing housing. I've replace plenty of stats in other cars over the years and the only issue is getting to it. Either way, I will save money if I do it myself.

What I need to know if my car has the new or old style.



As for the mechanic, I understand that he is in business to make money. I think his view is that for volvo owners who use him instead of the dealer, he is a bargain, which is fine. I expected it may go as high as $60 for the oil change, but 90 is outrageous to me. Even with synthetic/real blend, which is what he used, I can still get the same thing at jiffy lube for half the price. It could be that he spent time on the stat, and maybe he added some labor for that, which I would not complain about, but when I said "$90 for an oil change?" his reply was "that is what I get". No big deal, I am past that.


Now, when I drove the car the next day, the temp needle was all the way on the left and I had no heat to speak of, so I think he actually took out the old one and did not out it back in. Prior to brining it in, it went up about a third of the way.

 

From what I recall, the two bolts on top housing where the upper radiator hose (engine side) attaches is where the thermostat lives. They are usually Torx bolts.



My understanding is that they changed the design so that the housing (complete with thermostat) was replaced to prevent issues with the thermostat itself. If you can see the bolts and get the upper housing off then I believe the thermostat from an earlier year will fit fine.






Good luck.