Hi Scotty,
I have a 2003 toyota sequoia limited 2WD that I bought last month with 92k miles. I did a tune up on it, changed out the spark plugs, oil, transmission filter/oil, timing belt/pulleys, water pump, etc.
Recently I noticed that my coolant was low in the reservoir so I topped it back off to full. Then, after driving it a bit, I checked again and it would be back below the full symbol by about an inch. Topped it off again, and same thing. I got scared that it was the head gasket because I'd start the car cold in the morning and I'd see white smoke for like 15 seconds but it would go away (pretty sure it's condensation in the tail pipe at this point). I went ahead and did the head gasket test with that blue fluid and chamber thing, and it came back negative which was great. Then I tested the system with a radiator pressure test and I did indeed slowly lose pressure. I couldn't see from where though. The only fluid I saw leaking from the bottom of the truck was coming from this spigot thing that came from the back of the engine bay on the passengers side (see pic/video).
The fluid was not red nor did it smell so I have no idea if that's actually part of the cooling system or just condensation from something else? Any suggestions on what it could be? Also, I should mention that the truck still has the original radiator.
Video: https://youtu.be/HQ8dnu0f--Q
Pic: https://imgur.com/FcE6lkC
It could easily be a slightly leaking heater core which will have coolant come out there. So try this get the hoses to the heater hose of the firewall take them off and splice them together or plug them up then pressure test the system if it no longer loses pressure you know it's a leaking heater core I'd bet on that
@scottykilmer
Hi scotty, I gave your method a go and still got a small leak. I then tried the UV method with the dye and found nothing. I gave up and took it to a local shop. They found no leak. So I think either I didnt do the pressure test right (not a proper seal) or the tool i rented was no good either. Thank you for your help though. I learned a lot from this experience. I actually kind of like working on my car haha.
That's a body drain...likely a condensation drain for the air conditioning.
As to the coolant level. If you simply refilled the cooling system after your drain...you've got air in the system and as the air works its way out, the space it leaves will be overtaken by coolant...coolant level drops.
Since you have a small pressure loss...it doesn't take much to cause that...loose hose clamp, rotted hose, bad seal on radiator cap, pinhole in radiator (hard to see, look in upper and lower corners), thermostat housing gasket You may have to look for dried coolant on surfaces to find the leak...small leaks evaporate fast.
If you have any strong antifreeze odor inside the vehicle...it would be from the heater core under the dash.
