Rep Power: 0

I have a 2001 Honda Civic LX 4.0. My fiance decided to try and save money and replace the thermostate on his own.... About 2 or 3 days after this, my car started overheating while idling. He then realized he left the cap off of the coolant, he replaced it, but it had leaked out. It has NEVER done this before the thermostate was changed. It has done it off and on since then. However, we drove about 60 miles away yesterday. The a/c was on, never had a problem while on the highway .. but when we got off the exit into the city ... the temp started rising quickly. We pulled over and let the car rest for about 30 minutes. He replaced the thermostate w/ another new one. One the way home we didn't have a problem on the highway .. but when we got off the exit, speeds 30 miles ... it started rising slowly again. He also replaced the radiator cap that same night. He seems to think all of a sudden it is the radiator//water pump. But since this problem never existed until the thermostate was changed, I'm not so certain. Any ideas on what might be going on aside from radiator and water pump?

 
Rep Power: 231

I'm sure you've lost coolant from the cap being off or created an air bubble in your cooling system when the thermostat was changed. It sounds dumb but make sure the coolant level in the radiator is full.

 
Rep Power: 329

Top off the Radiator with Coolant, let the car set and run with the Radiator cap off and the heater on full blast for about 30 min.
Make sure the fans on coming on and keep an eye on the coolant level in the radiator.
What you will be doing is "Burping" the system. I bet he got an air pocket int he system. This procedure will help to get rid of it.

Good luck and be nice to your man for trying to fix the car, especially if this was his first attempt at something like this. Men hate being told that they are not good at things or that they should have let the "Professionals" do it. I think he deserves an apology, oral pleasure and a smile from you.

 
Rep Power: 0

Understand the guy that tried to do the work himself. Read below what a dealer would have done. I agree with the other posts. As Honda Service manual states: Top-off the coolant filling the radiator neck. Run the engine until coolant warms leaving cap off and heater turned up high to "burp" the systen. Hopefully the coolant was a Honda specified coolant.
I do work on the car myself except for warranty work. Here is one reason why: I planned to replace the engine coolant. Went to Schaumburg, IL Honda dealer parts dept. Honda Service Manual directs you to open engine block drain plug to drain coolant as well as open the radiator drain. Manual states replace the aluminum washer on the engine block drain bolt. Parts dept did not stock the washer! The Parts guy went to speak with the mechanics. He came back and said to me that the mechanics do not open the engine block drain when they do this work. So the Parts dept does not stock the washer. Obvious conclusion: So even though the dealer charges customers the "book rate" for the work which includes the time to open and drain block, customers do not get that service, their cars are not serviced according to Honda proceedures. And this dealer claims that they are better than non-honda service people/shops.