Does anyone know if this is normal. My cooling fluid has gone down by 50%. How do I test for leak? I am borrowing a cooling system leak tester, and my Acura is the regular 2008 TL, not the "S". What is the pressure test? What PSI and how long it must hold?
Can I use Honda coolant?

 

No, losing coolant is not normal.

When you say "fluid has gone down by 50%," are you talking about just the level in the overflow reservoir, or is the reservoir dry and the radiator itself also low on coolant?
When the engine is cold, open up the radiator cap and make sure there is coolant up to the radiator neck. If not, you may have a problem.

Are you comparing levels in the reservoir when the engine is cold and then when it is hot? If so, don't do that: the engine circulates coolant when running/hot, then dumps it back into the reservoir when cold. You'll see two coolant level marks, for "Hot" and "Cold"-- that's the "full" line for each of those temp conditions.

What is the period of time it takes for the fluid level to drop 50%, i.e. how much time passed before you noticed the drop?
If you cannot say less than a month, I'd fill to the proper level with coolant and monitor for further losses.

Do you smell a sweet smell from the radiator area? Check for leakage at the neck and where the overflow tube is attached.

Yes, Honda coolant is fine-- that's what Acura dealerships sell.

G/L.

 

if you confirm that you're losing coolant and it's not just because the engine is hot or cold, just take a flashlight and look around the engine bay to see if you can spot the leak. if there's a leak you can spot dried green coolant around an area if one of the hoses sprung a hole.

 

It is normal to loose a small amount of coolant over time but if you lost 50% (in your cooling system) then you have a problem. In your overflow its fine and just fill it back up.