Originally Posted by miketporsche
I didn't get it pressure tested at my Indy. I tested it myself with a Stant tester. No leaks appeared and the tester was not losing its pressure.
I did the pressure test with a cold engine. Is this the correct way to do it?
It is one way to test the system for pressure integrity but it may not turn up the leak.
Another way is a bit cruder but can help you find a leak, a leak I suspect very strongly your car's cooling system has.
The few times I've smelt coolant/anti-freeze there's been a leak.
Be sure the radiator cap is new. That was one leak.
If the cap is ok then drive the car around enough to get the engine fully up to temp. Run with the A/C off. You want to hear the radiator fans come on then after a while go off.
Once you've heard that once or twice head home and park the car in a convenient spot (one easy to for a tow truck to get access to just in case) and raise the rpms to 1500 and hold until the fans come on.
Then turn off the engine. The fans will stop running.
But the engine being hot will raise the coolant temp and its pressure. This coupled with things being very warm, soft, pliable, at their weakest...
It was doing this that made a slightly cracked coolant tank -- that would seep a few drops of coolant out which is what I was smelling -- finally fail outright.
After the car sat a night and got completely cold I drove it less than the 2 miles to the dealership where the old split tank was replaced.
Now the leak might not be at the tank, but at a radiator, or a hose, a fitting, and of course the water pump.
So you have to be handy with a flash light and ready to get down and look at places from where a leak might be. Listen too. You might hear a sizzle as hot coolant drops on hotter exhaust pipes.
Also, be careful. The tank in my Boxster split with no warning and had I been under it I would have gotten a scalding.