I have a 2002 Lexus ES300 that I bought for $3000 about 11 months ago. Since then I've put about 16k miles on it. It's been a great car with everything considered.
In the summer (around 163k miles) I was driving from CA to TX. While on the drive I noticed that I was slowly losing coolant. I couldn't directly pin point where it was from at the time. I decided to get a new radiator cap in NM because the one I had was the OEM one which was 20 years old. After that, I went a few miles and the radiator finally burst at the top where the plastic and aluminum come into contact. I realized it had been slowly dripping from there because of the staining. I had to hobble the car to a radiator shop while trying to not let the car overheat. At one point the coolant temp needle did get into the red before I shut the car off and pushed it the rest of the way with the hood open to cool it off. The shop replaced the radiator and I went back on my way. During the rest of the trip the car would sometimes be a little lower on coolant on different days so I would top it off to make sure it wasn't air in the system or something like that. Now its 5 months and about 8,000 miles later. My car still slowly loses coolant and I have to top it off sometimes. The expansion tank has no cracks, and I've never seen any drips below the car. Heater blows hot air (although it takes a few minutes to warm up). Only smokes white smoke on first start up during cold days. I just changed the oil and I'm not sure if this means there's coolant in the oil or not. I've attached pictures below.
What should I do from here?
Change your pressure cap
the main radiator cap that I already changed? or plastic cap on the expansion tank?
the one that holds pressure
even though I changed it with the new radiator?
should be ok then. A cooling system pressure test would reveal if there's a leak.
Or there's UV dye test kits.
I did the combustion leak test today and the fluid stayed blue and didn’t turn yellow i tried multiple times and did it for 2 minutes. kind of confused at this point. was expecting the head gasket to be leaking. i guess next is cooling system pressure test?
Did your perform a compression test or a dye test? Which one? They are two different tests. If the dye test didn't show anything, do the compression test. If that's good, then you know you have a leak somewhere. The leak test also uses a dye but you look at it with an ultra violet light to see where the leak is coming from.
i used the dye test on the radiator cap to check for gases in the cooling system.
So if there are no exhaust gases in the cooling system, the next thing is to pressure test the cooling system with and air pump and gauge to try and find the source of a leak. Or, get the proper dye, pour it in the cooling system, run the engine and with an ultraviolet light, see if it's leaking anywhere. Once again, if it is not burning, it IS leaking somewhere.
The coolant is either leaking or being burned. There are no other possibilities. Get a compression test. The head gasket is probably on its way out.
compression test for cooling system or for the cylinders?
just to add i was told last march that one of the cylinders had 125psi compared to all the others having 140-150psi. but that was literally 16k miles ago.
Compression test for the cylinders and a pressure test for the cooling system.
ok