2poor2mod

had a similar situation on a customers car a while back, it ended up being the water pump. The fins on the blade of the water pump had corroded away, giving no flow at idle, there was enough left to the fins that when moving at high rpms it would still circulate the coolant though. While you're in there you might as well replace the timing belt and balance shaft belt as well.

fatjoe10

Remember that sometimes a leaking/seeping head gasket will not show any symptoms right away. I once had an issue with cyclic overheating as you described. It turned out to be a headgasket. I'd do a compression/leakdown test at this point, assuming the car has been overheated many times.

sahtt

Yikes mechanics scare me. Must be related to the fact I do all my own work these days.

First of all, there shouldn't be any "guessing". The coolant is old and needs replacing or it doesn't. Coolant temp sensor is tested and in spec or it's not. The thermostat is either staying open when it's not supposed to or stuck shut or it's not. The radiator can be pressure tested and checked for leaks as well. My guess is you just randomly replaced these or had your mechanic replace these.

Your mechanic is a goof ball. He should have at least strongly suggested for you to have a compression check done to test if the head gasket is in decent shape. He shouldn't charge over 100$ even at rip-off prices. You canNOT tell if your HG is damaged or blown unless you have a compression check or have your coolant analyzed chemically.

After a thorough diagnosis if nothing is revealed it will probably narrow it down to the WP. The coolant system is actually relatively system.

sahtt

On another note, if it overheats while moving at a decent pace there is a higher probability of a WP/sensor error etc.

If it is only over heating while stopped in traffic, that suggests to check the electronic fans more closely to make sure they are coming on and the fans aren't all broken or something.

Act of God

The temperature never raises if the car is moving. If it does overheat all I have to do is drive it to make the temperature go down. The fans are going on as needed every time. There is definitely no problem with the fans. We monitored them for a while and they always clicked on/off as expected.

I agree about my mechanic, it is just the only place I can walk home from. I think I might try another local place, though, because this is just ridiculous at this point.

Like I said, I'm dumbfounded but I'll try one more mechanic. I'm trying to avoid going to the stealership though...

JonBoy

A friend of mine has this exact same problem. He's figuring water pump at this point but that's a moderately expensive fix... Definitely fill us in when you figure it out.

Act of God

I'm starting to wonder if it is a common problem with that particular generation of civics...I've been checking a lot of forums and I am definitely not the only one. I've yet to see a solution though...

curiouz_G

ive got a 03 civic so maybe i can shed some light on this issue.

it does seem like a typical head gasket issue. the head gaskets on the d17 are very weak but at the same time, very strong. one of my friends making close to 500whp on the SOHC d17a2 is rocking a stock HG and hasnt blown it. id just open the cap, pump the heat up, and see if it burps air continuously. if there is, then its a HG. youd also know by white smoke coming out, alot of coolant spilling into the overflow reservoir, or even you needing to keep filling it with coolant.

one good thing about this car is a motor with 50k-70k miles (the block) for about 500-700 dollars, which is way cheaper than paying 1000 to 2000 to fix a bad HG since i assume the motor isnt built or modified.

curiouz_G

another thing to try is to check for oil in your coolant. also, check your coolant hose to see if its hot or cold. try doing a cooling system flush bc it might be clogged. last but not least, you can do a compression test.

civicson234

I had the same problem on my civic. It was a 95 DX hatchback. Changed my headgasket myself, and the problem went away. It would overheat at idle, fans would come on, id drive it and the temp would go back down. Only clue i had to a leaky headgasket was that i had to keep refilling my coolant. It was leaking outside, onto the block, behind my intake manifold, so i couldnt see it. The leak was letting air into the coolant system, which heatsup faster then liquid, causing it to overheat. To do the work, i used a haynes manual and basic tools at my house. Cost me about a grand total of $50.