Curse you coolant!
 

I am wondering why my car leaks coolant sometimes and other times it is fine.

I have a 1993 with 83k miles. Last weekend, I took it out on Saturday and Sunday around here locally in the Santa Monica/Culver City area. The temperature was warm but not very hot. It was a lot of stop and go driving mostly. I park the car and no coolant leaks at all.

Today I took the car inland and the air was fairly warm and the temp inland was probably 85 degrees or so. This was all highway miles at about 40 miles one way. I park the car after I get home. Several hours later I go to the garage and there are two coolant puddles under the car. One under the passenger side and one under the driver side. I checked for busted hoses and found nothing. I smell the faint scent of burning coolant. The coolant level is normal. What the heck is going on?

The car has an aluminum AST and it hasn't overheated at all.

Your coolant seals are most likely failing. Bad coolant seals means you will have to get your motor rebuilt.

Those intermittent coolant puddles under the passenger side mean that you could may have coolant seal leakage and small amount of exhaust gasses are getting into your coolant. This will then cause the coolant to be pushed into the overflow tank on the passenger side.

There are testes that you can do to be sure that this is or isn't your problem. You have to search for those as I haven't done them myself.

Sorry to be the bearer of the bad news.

I had something like that...sometimes it would leak, sometimes it wouldn't...I had the stock AST...turned out to be the AST leaking partly at the seam and two hoses with a very slight rupture, hence did not leak so much coolant so as to be noticed always. Eventually though they leaked more and more. I also changed the pressure cap.
So if I were you, I would check very carefully all hoses, maybe check the pressure cap as well, before you start thinking of other causes...

Thanks jpandes and Riccardo. In the back of my mind the bad coolant seals idea occurred to me, but I am praying this isn't it.

I will have to take it into the shop and have them check all hoses and the pressure cap. Thanks guys.

I used to have that dreaded coolant under the coolant tank after I parked. I refused to belive it was a coolant seal because there had been NO previous evidence of such. I changed every coolant hose, coolant tank, new aluminum AST, new caps, new thermostat, and what do you know, runs fine.

Make sure they are thourough, especially if it is a little split. Good luck and let us know what happened

I hope it's not your coolant seals. That's expensive! I know.

Hello,

Got my car back from the shop. They replaced the AST cap and the radiator cap. All hoses were fine and they pressurized the system and it was ok.

Yah! Thanks again for the suggestions and help, you guys rock! :D

excuse me for being ignorant, but whats an AST? I've had my FD for about a month now and have about 5mins of seat time. Ive noticed theres alot of pressure building in my radiator. Could this be bad coolant seals? I still havent seen any puddles yet though. thanks

AST = Air Seperation Tank.

It does at it says.... separates the air from the coolant. (allows the air to escape) through a pressure cap. It's located behind the left side of the radiator and intercooler. If I'm not mistaken

Victor

thanks, I appreciate it.

Technically it is not "air" but bubbles of vapor produced in the cooling of the engine. It is actually intended to remove these gas formations (coolant and water vapor). It does remove air from the system also that may be trapped in the system (eventually).

Tim