cdy_626

Hey guys, I started to notice last week that my car starts overheating while in idle but when I start moving the temp will go back to normal. And it will also go back to normal if I put the car on neutral and rev the engine. And also I a few months ago, the fan would run for like 10-15 minutes after the car was shut off and now it doesn't do it all the time, just sometimes. I changed the fan relay. But it still doing the same thing. I also haven't had a chance to see if the fans go on on time with the engine running. Does anyone think that the overheating might be due to a delay in the fan and maybe a bad thermostat or the radiator fan switch? I also noticed today that there was coolant splattered by the radiator, on top of the coolant reserve tank and by the intake. I haven't had a chance to check for broken hoses yet. Any suggestions?

saiko_cl_duck

check for broken hoses first and always. Check to make sure you're not leaking fluid (hoses, cap, drain plug), it's a quick and easy check. You can take the thermostat out and check it, and it's a cheap replacement.

Check to make sure you don't have a puncture in your radiator. check your coolant level also. Now would be a good time to perform a radiator flush.

cdy_626

Haven't had time to check it out nut I definitely know there's a leak somewhere cuz i saw coolant on the bottom of my car today.

bRunCL

iTrader: (1)

could also be a cracked radiator (happened to me before). imo i would try to get it figured out sooner than later because eventually you will loose all pressure/coolant and will have to get a tow.

cdy_626

Yeah, taking it to the shop first thing tomorrow to get it checked.

cdy_626

Problem solved. It turned out to be a small hose by the firewall of the engine and a bad radiator cap.

cdy_626

Might have spoke too soon. There's a leak in the same place but no overheating. Could it be another hose or maybe a slow leak in the thermostat gasket? Any suggestions?

cdy_626

This is a pic I took when it was leaking more but this is the same spot where I see the coolant leaking to. Just to give an idea to if it might be another hose around the same area or the thermostat gasket.

saiko_cl_duck

Drain you radiator completely.

Then take off your lower and upper hoses and bend them to check for cracks. They may look good, but when you bend them slightly, you might see that the rubber is cracked. Also, check to make sure your petcock on the radiator itself is working properly. I just replaced the one on my wifes car for slowly leaking.

Have you taken off the thermostat housing yet? A bad seal on that can cause leaks/spraying.

cdy_626

It turned out to be another small hose around the same area. I'm having the valve cover done next week so while that's getting done, all the small hoses will be replaced.

D2Coupe

I just noticed that my coolant is leaking a bit, but there is still fluid in the res. should i be concerned? the temperature just dropped out here so im not sure if that why?

PMRacing

I hope this helps, because when I had the problem, I looked through many threads here and in other places with lots of different advice which didn't really help. I believe this to be common as many people have same symptoms and no real fix after changes (ie. thermostat, fan relay, fan timer, fans, sensor, radiator, guage, etc). The car only temporarily is fixed as more fluid is added, as much of it leaks out from expansion tank due to overheating.

The problem here is your water pump. The symptoms commonly seen is overheating in idle, or at lights, but as soon as car starts moving the temps drop down. This makes it seem like its the fan is not working as air is not flowing through rad until car is moving. But the problem is the water pump, its shaft in particular. (The empeller and pulley are not linked like before). This is why when moving will help the car cool down, as the higher rpm causes the pulley to turn faster, and thus causing the empeller to turn by just virtue of rotational force. A way to test this is to run the car until it is HOT, then speed up quickly and coast (helps if there is a steady down hill), usually costing should cool down the rad if air is flowing, but unless you keep your rpms up your car will be showing hot constantly. Hope this makes sense let me know if you have any questions, I just signed up as I am a frequent visitor and haven't seen a clear answer to this common problems on the forms and hope it helps others!

PS here is a vid of the shaft and pulley, it may answer what i am trying to refer to.