After several months of lurking, i'm finally making a post! I've owned an RX a total of about 3 weeks. I bought used w/ about 41k miles. looks great, runs great. problem is, the local Toyota dealership (Lexus dealer is about 90 miles away) says I've got a coolant leak somewhere (reservoir was just about dry). Any help is greatly appreciated.

 

What I would do to test this theory is fill up the coolant reservoir to the full line with bottled water (not the fizzy stuff). Also, where exactly is your temperature gauge after you have warmed up and driven for at least 15 minutes?

and before I forget, Welcome to Club Lexus

 

Have the cooling system pressure tested. The problem could be a leaking radiator, hose or water pump.

 

Do the test, watch for leaks. It has to go someplace, not into thin air.

 

Personally, I would specifically get *distilled* water for this.

 

Yeah that is the best stuff. Is there is a specific brand you use?

Down here, I use one called electropura.

 

If you are just filling the system up to find a leak, tap water will work. Once the leak is discovered and repaired, THEN you fill with fresh coolant and distilled water.

 

hey man where in illinois are u located? what toyota dealer? im at libertyville toyota i'll check it out for u. we got gallons of extra red coolang laying around i'll gladly let u use/put in in for u

 

Thanks for all the responses. I'm hesistant to introduce water of any kind (though I realize it's a 50/50 mix) right now. I bought some premixed coolant from Wal-mart (the stuff seems to be universal, though I'm not sure about "organic acids") to have available, should I be running low again. It must be a very slow leak, as I've been driving reguarly for 6 days, and the reservoir is still at max level. The engine has never overheated, though I haven't taken any long trips in summer weather yet. Question is, should I be concerned or just monitor the situation for now? I have a tenative appt w/ the Lexus dealership, but don't want to pay a high diagnostic fee to find out it was some kind of fluke.

 

Just keep an eye on it and pressure test it the next time you are due for service.

 

When I do my coolant changes every year, see https://www.clublexus.com/forums/sho...d.php?t=249741

I encounter the fact that even though I know I drained the whole thing (I can measure it), I encounter empty reservoir issues for a few days after, and I have to fill it up with water each day up to the full mark, then things level off an no issues.

 

Lexmex, thanks a bunch for this link. I am fixing to do my drain and fill soon.