I have a 2012 Hyundai Sonata with 95,000 miles. My coolant is obviously draining somewhere. Every 5 - 7 days the coolant lowers from the full line to low line. The Hyundai dealership completed a diagnostic/pressure test but could not detect a leak anywhere. Any advice or ideas?
No white smoke. About 6 months ago, the place I took the car to for an oil change also did a coolant flush. They forgot to attach the hose and coolant coated my engine. Needless to say, it always has a hint of coolant smell. Not overpowering though now, so I don’t think there is any new coolant burning. I will keep an eye and nose out for both things you noted however. Thanks!
How many times you did coolant top off? It's normal to top off 2-3 times after flushing, then when you mix different concentrations of coolant the total volume becomes smaller
Does the heater inside work? Does the engine temp seem normal or running higher? Also, are you adding it to the expansion tank OR directly into the radiator?
Unless it's now going into your engine our still dripping out, it sounds like they didn't bleed the system of all air (especially after they messed up).
If you're able to, park car on incline, let cool down, open radiator cap, add coolant, start car and let ildle while squeezing upper rad hoses. Keep adding coolant as it goes down and air is displaced. When bubbles mostly stopped, close radiator cap and fill expansion tank.
You may need to repeat this once or twice. Reason your expansion tank drains is back half of your system that's opened and closed by tstat stays closed until engine warms up. At that point, coolant from rad flows in and displaces some of the air. Now that rad is low, expansion tank fills radiator. And the whole thing repeats... 7 times.
Actually, scratch all of the above. The shop that did the job should really deal with this; not you. Unless you don't trust them to check it out again, I'd take it right back and describe the issue before you touch it some more and they claim you caused the issue.
I would strongly suggest you also have them (or a trusted dealer) do a pressure test (while warm) to ensure you don't have a gasket leak (at the heads, etc.) into the engine which can cause all manner of bad news!
Tiny cracks in the head gasket ( I have had this issue) would only appear in cold weather when the engine cooled at night the gasket would contract and the coolant would be sucked into the cylinders and be burned at start up in the AM,. No coolant leaks could be found, pressure test when warm was also fine, no coolant in oil etc. . No problem in the summer months but every winter the coolant level would drop consistently and I would add a sealer to get me through the winter and all would be fine again. My son currently has the same issue with his Altima. Just saying, a possible scenario but not sure where the original member lives, is it cold enough in the winter for the cracks in the gasket to contract and open up etc.
Need to know which hose they took off / or how they did so called flush...
Only real leak concerns I have seen with the 2.4 / 2.0T is the heat hose at fittings on back of head,, they like to seep when re-install and factory spring clamps re-used,, even when setting clamps back in original location via impressions on hose...
Some times you have to just do a good visual and find the stains, as coolant at very slow seep will evaporate and not have chance to make it to floor on a hot engine.. look for green-white chalk stains.. finger around ends of hoses at fitting for seepage.
@#14
I don't put new clamps on, though one could and that would probably alleviate the problem. I reinstall the heater hoses and then twist (rotate) them back and forth on the nozzles. This reseats them better though they still sometimes leak.
After a few years and 100k the factory clamps loose tension and leak, usually on cool down and no pressure though. Look for moisture or dried coolant stains at the hose ends.
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