Thread: leaking coolant

Please help. This problem is on a 2002 GTP with 132,000 mi. I have been leaking coolant for a few months now. I have replaced the radiator cap, thermostat, water pump, and the coolant tube to and from the heater There is no coolant in the oil. The car is still overheating. There is pressure in the cooling system, when it overheated today I added a lot of water to the system.

First, lets get some details.

1. Any sign of an external leak anywhere?
2. How do you know there is no coolant in the oil?
3. Just because there is pressure in the system, it may not necessarily be enough.

There are other places there could be a coolant leak at as well, namely the LIM or the throttle body, and it could be a bad radiator too. If you have any more information you can give we might be able to narrow it down.

If you can smell the coolant leak, odds are its leaking out externally. If you look around for some white maybe chalky looking streaks, that is where coolant has been and evaporated.

Depending on how much you drive on the highway and how severe the leak is, draining the oil and only getting 4.5 quarts is not a solid indication. If you drive long distances on the highway, chances are you are getting things up to temperature enough to evaporate any coolant out of the oil. But if its a severe leak then you wont be able to do that. So that at least tells me that if you do have an internal leak that is getting into the oil, its not a horrible one at this stage. The other way to check is to pull the dipstick after you park the car and see if the oil on the dipstick is milky looking.

You wont 'feel' any flow through the top radiator hose unless the thermostat is open and for that to happen the car has to be up to operating temperature and then its going to be so warm I would think it would be difficult at best to hold on to that top radiator hose to see if you can 'feel' any coolant flow. Since you mentioned replacing the thermostat, I will assume it is good, but also ask did you bleed the system of air? If not that could be an issue.

Lastly, I dont know that you can measure for proper pressure aside for doing a coolant pressure test which I believe has to be done with the engine cooled down. I believe you can get the tool in the parts stores to carry out that test but Im not sure how much they cost.

Since you have replaced so much already Im thinking either your radiator is hosed (look for evidence of a coolant leak around the plastic tanks) or you perhaps you havent bled the system of air, at least thats all I can think of right now. But the fact you can smell coolant is something that needs to be looked at as well because if you can develop full pressure, you will overheat easier or run warmer. You can take it to a shop and they can use an infrared thermometer and see if there are any hot spots in the radiator that could indicate the thing is clogged somehow. Im sure they could do a pressure test as well.