Alright, here's my story. I have a coolant leak...somewhere.

Around a month or two ago I had a radiator that was leaking from the top tank. Replaced it with a Mishimoto radiator and Mishimoto upper and lower silicone radiator hoses. Also replaced my coolant overflow tank with a JMF one. Refilled and didn't have any issues.

However, a few weeks later while driving I noticed my temperature climbing dramatically. I get home and open the radiator and notice I lost A LOT of coolant. Like a gallon or more. Refilled and the problem disappeared for a month or so.

I had to replace my throttle body shaft seals recently (within the last month) -- so the throttle body came off the car. During reinstall, one of the hoses from the head/block was ripped.
As a result (and after some research on the forums) -- due to my climate -- I removed the two coolant hoses from the throttle body and capped the throttle body nipples with vacuum caps. I then took some hose and looped it from the block to the head to recirculate the coolant and remove the throttle body circulation from the system.

I have also (about a year ago) replaced the heater core hoses after doing some HVAC repair.



So I have checked most of the system and replaced many components on it.

My leak isn't constant. The weather doesn't seem to factor into it. I have been regularly checking the car (at least once a week) and there is no consistent evidence of leaking. When I do see water/coolant it usually falls near the back of the firewall around the front tires. And I can see residue on the downpipe.

I have consistently checked for leaks under the car as well as running my hand (as best I can) under the intake manifold and checking hoses.

Just yesterday I noticed a fair amount of water around my car when I came out to it and this morning the car was getting hot again. I had to add another gallon of coolant.

So...any ideas?

 

Any signs of the coolant mixing with oil? Sound like your loosing a lot of coolant and if you cant track it down it could be possible that your headgasket is leaking...

 

I am about to do an oil change soon but I haven't seen any white smoke or smelt anything. I plan to check the oil once I change it. (It will be the first time since the install of the new items)

 

The next time this happens, check the overflow tank. If it is full then the head has lifted.