Q: Leaking coolant no signs of leak anywhere 2006 Scion tC

asked by on January 28, 2017

i am leaking coolant from somewhere have to add to radiator after every trip but reservoir stays full. checked all hoses they are fine, oil is clear not milky, no residue anywhere that i can see. new thermostat. heat works great when driving goes cold when idling, passenger carpet dry and no smoke out of vents, or white residue on windshield. car runs fine when driving doesn't feel like it is misfiring.

My car has 118000 miles.
My car has an automatic transmission.

Hi - this problem sounds a bit more challenging as you have done all the logical things - well done! Remaining possibilities include coolant leaking into the exhaust (cracked cylinder head) which would give you white smoke with a sweet smell out of the exhaust. The remaining choice is a very small leak that is drying before it drips. It will leave a trace over time, but may take a while. A small leak like this can be discovered by adding an ultraviolet dye to the coolant, let it circulate enough to become thoroughly mixed with the coolant, then use a black light to help discover where it’s leaking. I recommend acoolant leak inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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