Car:
1992 Z28, automatic, AC

Problem:
I started up my car and kept it going until the fans came on. I noticed coolant leaking from the outside around the firewall area (onto the floor) and it pooled up inside the passenger side floor also. It appeared to be quite a lot coming out from the outside and slower in the inside.

What I've done:
I did a vac test and once it reached 20psi, the needle started to come down very slowly (approx. 1psi per 1-3 mins.). Some coolant came inside onto the passenger floor again due to the vac test. So I have a leak somewhere, but it appears to be a small leak? After the leak, the floor was wet around the area underneath the car so I couldn't really check it out. I've run the car before, but not as long as this time and it has never happened. This was the first time I let it run until the radiator fans started up.

Questions:
Is it possible for a small leak to let out a lot of coolant? Are there any coolant hoses going into the firewall or under the AC condenser plastic housing thingy? Any other suggestions/tips? I know this is a lot of stuff I wrote, but I appreciate any help. I'm not a mechanic either. :-)

I got this car in non-working order. I occasionally start it up and let it run for a little just to get things moving and wet, but this has never happened before.

 

Sounds like you have a bad heater core. The two hoses that go to the fire wall just inboard of the AC box circulate coolant thru the heater core under the passenger side dash. You can temporarily by pass the heater core by connecting those two hoses to each other, but you will no heat or defroster. You will need to replace the heater core to recover those functions. There are write-ups on how to do that if you search this forum , but it is not a fun job.

 

Ugh, not what I wanted to hear, but thank you very much. I will check into it.

I guess I'll have to add that to the list...hmm, number 1532...