Mechanics

COOLING FAN/OVERHEATING

2002 Honda Civic • 120,000 miles

I was driving my car on the interstate, and my car started to over heat. I turned off the engine, and it would not start after cooling down. Ihad it towed to a local place who told me my cooling fan was busted and possibly could have a blown head gasket, because there was coolant on the engine and steam coming out of the radiator when he would try and start the car.I then had my car towed to my mechanic who ran a pressure test and found no leaks. He fixed the fan and said the car didnt overheat when he test drove it. I picked it up today and my heater would only blow warm air when I was at a high rpm, and then my temp gauge kept going up and down. It runs, but there is definitely something wrong. Any suggestions?
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Zimmer7
May 1, 2013.



Yes, you have a blown head gasket. Have a leak down test done to confirm.

Roy

Leaking cylinder head gaskets often don't show up with a pressure test, especially after the engine has cooled down. The best way to identify them is with a "sniffer" test. That involves drawing air from the radiator through a glass cylinder with two chambers partially-filled with a special dark blue liquid. If combustion gases are present that liquid will turn bright yellow.

When combustion gases leak into the cooling system fast enough they can pool under the thermostat and prevent it from opening. Thermostats open in response to hot liquid, not hot air. That is likely what started all the trouble. Your radiator fan may indeed have been bad but it is not needed at highway speed. A fan that doesn't run will not cause overheating at higher speeds when you have natural air flow through the radiator. A leaking head gasket can cause overheating at any speed if the thermostat closes and blocks coolant flow to the radiator.

The two additional clues to a leaking head gasket are the temperature gauge going up and down as the thermostat repeatedly opens and closes as the air pools under it and it gets hit with hot coolant sloshing around, and the reduced circulation brings less hot coolant into the heater core in the dash so the air won't be very hot.

Caradiodoc
May 1, 2013.
That's not what I was hoping to hear. I'm calling the shop I go to in the morning. Any idea how much it would cost to repair. Or is it even worth repairing?

Tiny
Zimmer7
May 1, 2013.
Leaking head gaskets are common on many car brands and it can happen on much newer ones. There's a lot of variables in the cost of repair but a guess would be between $500.00 and $1000.00 which is a lot less than a few months worth of new-car payments. Your mechanic will likely also want to replace the timing belt. It will be off already, and if it breaks the cylinder head will have to come off again to replace bent valves. Honda used to recommend the belt be replaced every 75,000 miles, and they typically broke at 65,000 miles leading to a lot of expensive repair bills.

I personally would rather stick money into a 2002 model anything than buy any newer car. Some of the new technology is nice but a lot of it is inappropriate for cars. That's why I refuse to give up my '88 Grand Caravan. I have three newer vehicles but I don't trust them as much to get me back home. Look at how much trouble we have with home computers. Cars may not let you sitting on the side of the road as often as they used to, but look at the expense people go through when a computer failure causes things like no power windows or lock, or the heater system doesn't work right.

Caradiodoc
May 1, 2013.
Thanks for the help. Ill give you an update when I find more out tomorrow.

Tiny
Zimmer7
May 1, 2013.
So I finally got my car back today, and they say my PVC valve was causing all the problems I was having. Car seems to be running fine now. Could this have been tha cause of all my earlier troubles?

Tiny
Zimmer7
May 6, 2013.
Pcv does not effect overheating or cooling fans

roy

If I do have a blown head gasket, would my car be running fine or running at all? Heater/ac work and temp gauge is steady.

Tiny
Zimmer7
May 6, 2013.
As I suggested early on, have a leak down test done to verify. Do not use the shop that told you a pcv valve

roy
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I did have a head gasket out. Got everything fixed for a reasonable amount. Will never go back to the original shop I took it too. Thanks for your help. One more question though, maybe I never noticed this before but when I'm idling I have a little shake. Nothing too major, just enough to notice. Any ideas?

Tiny
Zimmer7
May 13, 2013.

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