2002 Civic overheating when stopped.
 

My 2002 Civic started overheating, when I was stopped in traffic for a few minutes. I took it to two different mechanics, and one said it was the head gasket, and wanted $650 for the job. The next mechanic I took it to said it wasn't the head gasket, cause it would be sputtering oil and coolant when we tested it. He thinks it's the water pump, and said that he'd change my timing belt (it's got 83K miles on it) and fix the water pump for $450. Any thoughts?

You need to do some troubleshooting and research. Head gaskets could exhibit a lot of different symptoms, not just "sputtering oil and coolant" - whatever that means.

Head gasket failure can lead to air in the cooling system, burning cooling or oil, or oil/coolant mixing together. All of which are bad. Air in the system can cause a motor to "overheat" at idle since the air rises to the top of the system, usually where the temp sensor is.

It seems like your mechanic doesn't want to go back and forth with you on this seeing how he now wants to do the water pump/timing belt. It's a business. Unless you have paid him for diagnostic work, he has spent time with you and hasn't seen any money from it yet. If the pump was bad, you may see an overheat at higher rpms, not just idling.

Do the fans turn on when the car begins to over heat? How quickly does the temp drop back down once you start moving the car again? Have you checked the overflow reservoir to ensure it is at the correct full mark? with the car cooled off, remove the radiator cap - is the radiator full of coolant? If not, do you see coolant on the ground after leaving the car overnight?

Thanks for the reply! This happened before, the last time we had hot weather in NY, and the mechanic made some minor repair on the gasket, and only charged me $75.
Now it's happening again as soon as we had temperatures hit about 90f. I didn't notice if the fans turned on when it began to overheat, but as soon as I started moving the car again, the temperature would drop down to normal. I didn't check the overflow reservoir, and haven't noticed any coolant on the ground, but the last time this happened, he added two bottles of coolant. I'll mention everything you said when I see him tomorrow. I kept asking him if it was the head gasket, and he insisted that it was the water pump.
Thanks again!

I just dropped it off to him after reading your post to him. He kept insisting that it was the water pump, because when we were testing it out, the top hose got hot immediately, and the bottom hose stayed cool until a few minutes later, when it got as hot as the top hose.

Let us know how it goes with the mechanic. Both hoses getting hot is a good sign that the thermostat and water pump is working properly (at idle - a water pump will increase in speed with engine revs). The upper hose will always get hot first, followed by the lower once the thermostat opens.

As for the small "repair" to a head gasket - that's not possible. It's either good, or bad. It's a flat piece of metal (for the most part) that prevents oil/coolant/air from mixing. There's no such thing as a small fix in my opinion. If you are slowly burning coolant off, the only fix is to find where t's entering the combustion chamber - most likely the head gasket. A water pump is not going to help in that situation. Now the problem may go away for another year since the system is topped off again, but won't prevent it from coming back.

Being low on coolant will definitely cause some of these symptoms. If you are not seeing coolant on the ground, then it's burning off. There's no other explanation for the loss.

He replaced the water pump and timing belt, and even fixed my exhaust system for $450 cash. I took it for a ride, and it was fine.
He said he saw the same symptoms in another Civic, so he didn't think it was the head gasket. I don't know what he did a little fix on earlier, but the overheating seems to happen in hot weather, and it's still very hot now, and the needle wasn't budging when I was stuck in traffic yesterday.
Thanks for the concern. I hope it's not going to come back next year, but at least I got the timing belt changed on a seventeen year-old car!

It just atarted overheating last night again. I brought it into the same guy that replaced the timimg belt and water pump, and he thinks it's a coolant leak. I looked at my regular parking space in the garage, and there does seem to be traces of a coolant leak. He's going to look at it tomorrow to try to find the coolant leak. I asked him about the head gasket again, and he said the way the engine is running, it shows no sign of a head gasket problem.

Appreciate the update, however, I'd be leery of this mechanic if he suggested a water pump but missed a coolant leak large enough to cause these problems only after 2 weeks. It may be seeping slowly, but if you have been seeping for this long there should be coolant stains somewhere. Good luck

He put the car on the hydraulic lift, and showed me the green stain where the coolant was leaking from, which he said was from the thermostat housing.
He said that when he replaced my water pump and timing belt, he noticed that there was corrosion on the thermostat housing, causing it to be not flush with the rest of the thermostat, so he's going to file down the housing until it's flush, sealing the leak, or if that doesn't work, order a new thermostat housing, which he said was inexpensive.
He maintained that the water pump was bad, and needed to be changed.
He said it was alright to drive until Monday, when he's going to do the job, because the car was too hot to work on Friday.
I got caught in a bad traffic jam on the Van Wyck Expressway, and the needle didn't budge. I have another job Sunday, and I hope it holds out.
He still doesn't think it's related to the head gasket!

If the cooling system is drained, the lower radiator hose removed, and the thermostat housing is removed, why not replace the cheap thermostat while you are in there? It would be a shame to do all of that work twice just because you were trying to save $20 from the start. If you are unsure of how old that Tstat is, might as well replace it, right?