[Car Experts] Need help with a question about my car!

So my check engine light on my 2001 VW Jetta come on the other day and I decided to take it in for a check-up. I was under the impression that it was due to my Catalytic Converter since it I was told about it not functioning proper the last time I took it in, but did not want to get it fixed because of their asking price.

However, they recently sent me a notice that it the part was on federal recall and the would fix it for free. I tried taking it in before, but they told me to wait until the light comes on to bring it in.

I take it in today and they call me and let me it that their are two problems with the car: the Cat. Converter and my thermostat. Now the question I have is what the exact use of the thermostat is? I tried reading on it online, but can't find out what the consequences of having a faulty thermostat does to the car. The reason I am worried about this is because I did not get it fixed and on the way back home from the dealership, I noticed my car was starting to overheat. I just want to be sure that it is not directly related to the thermostat. If it is, then I will take it to my own mechanic to fix it for much cheaper than the dealership. However, if it is due to something else that the dealership did when checking my car, I want to give them a call first thing tomorrow and let them know so that they are aware of the problem.

Thanks for the help in advance. So freaking frustrating!

 

Thanks for the reply.

I just called Pep Boys and the VW dealership and they both comfirmed that more than likely, it is a direct result of the faulty thermostat. I found the part at Pep Boys for $24.99 and I will take it to my mechanic to get it fixed first thing tomorrow.

 

Ok, he is an update on the situation and if anyone else can help me a little further, it will be greatly appreciated!

I was able to take it to my mechanic and told him that the dealership told me the thermostat was faulty and causing the car to overheat. He replaced the thermostat for me, but when he called me to pick up the car, he told that the thermostat was old, but it was working and the overheating was a result of the thermostat.

I was really pissed off at the dealer so I called them back and after multiple messages, I was able to get a hold of someone. The guy tells me it is not their fault because if I had paid them the $300+ they had asked to fix the presumed "faulty thermostat" they would have replaced and found out it was not the thermostat causing the overheating and that they would have told me what was causing it. Then I could have giving them another $400+ to get that part fixed!

So after further research on the internet, VW forums and various mechanics, I have come to the hypothesis that it is either the water pump or a cracked hose causing the overheat.

I have two questions for my Clutchfan car/VW experts:

1. Is there any way I can pinpoint the exact cause of the problem? The dealer wants another $180 to tell me what the problem is (even though they had got it wrong the first time) and my mechanic said he could do it for free, but he won't be able to schedule me in for another 2 weeks!

2. How hard is it to replace the water pump/cracked hose? My dad is very good with his hand and very experienced with cars (mostly Hondas though). VW is a bit more difficult to get to certain parts. I have found some DYI write-ups on VW forums, but they usually aren't for water pump/cracked hose. They usually incorporate changing the belts and other items.