My 2005 Acura TL is running hot. We have replaced radiator coolant fan heater adjustment valve and thermostat .. what could be mak

ANSWER : Thank you for your question. We can definitely help you. The only way coolant can "disappear" in your cooling system is through an external or (less common) internal leak. YourMechanic can pressurize the cooling system when cold (so it is safe to work on) and then look for the leak and repair it. Once repaired, your cooling system should be checked just to make sure you don’t have additional issues such as a stuck thermostat which can cause overheating. Please note that overheating an engine will eventually damage it (the head and block get warped from high heat) and if the overheating is severe enough the damage can be close to "instantaneous". Consequently, a problem of this type should be fixed ASAP to avoid additional problems. We would be pleased to have a certified technician from YourMechanic come out, and diagnose your overheating issue as well as make the necessary repairs.

ANSWER : There could be an issue with the cylinder head gaskets. Antifreeze can break down and become acidic if not replaced as normal maintenance. The head gasket material erodes and can cause engine compression to build up in the coolant system. This will prevent the flow of coolant which can create an overheating condition.

There is a test that can be done to check whether there is carbon monoxide in the coolant system; it involves special equipment.

I recommend having your overheating condition inspected, and perhaps have a block test performed.

ANSWER : Hello, thank you for writing in. The vehicle is reading normal temperatures because the fluid temperature sensor needs to be in the fluid to give an accurate reading. The second there is a leak and the fluid level drops, that sensor is reading air, and the gauge is giving a bad reading. Coolant leaks can be internal or external. For that reason, you must not rule out the option that your vehicle is consuming the coolant. This most commonly happens when you have a bad head gasket. In this case you will usually find white smoke (steam) coming from your exhaust. The leak must be at least partly external, because of the puddle you are finding. The only way to resolve the issues is to find and fix that leak. A dye test may be your best bet, which you can do at home with the right tools, or by a technician. For more help with finding and fixing the leak, contact our service department to schedule an appointment.

ANSWER : Hello, high idle can be represented by many conditions. A heater core would not cause this unless you have a coolant leak and the core was leaking. There are tests that can be performed to test a water pump (coolant pump). A vacuum leak can create high idle and even a high engine temperature. A suggestion is to read engine data and any fault codes in the system. This is done with a scan tool. The scan tool can read data which will give you information on the operating systems of the vehicle. If you’d like, a certified technician from YourMechanic can come to your location and do a complete evaluation of the overheating issues.

ANSWER : Hi there. When the heater doesn’t work, it’s commonly accompanied by an overheating problem. This could be caused by a broken heater core, a clogged heater core or perhaps as you’ve indicated, a broken head gasket. I would highly recommend that you have a professional mobile mechanic complete a car is overheating inspection so they can pinpoint the source of this issue and recommend the right repairs.

ANSWER : Hello, thank you for writing in. The engine coolant temperature sensor is a critical part to how the vehicle will run the fans, and that needs to be addressed first. Secondly, we need to make sure the water pump is pushing enough coolant through the system to keep up with the heat transfer that is needed to cool the engine properly. This can be tested several ways, and may require some special tools depending on how you decide to go about it. Replace the water pump if needed, and take any further diagnostic work from there. For more help testing or resolving the issue, contact our service department to schedule an appointment.

ANSWER : Hello, thank you for writing in. Everything that has been done was valid in trying to trace down the issue. You likely did your vehicle a lot of good in updating those cooling system components. With that being said, one of the only components you did not mention testing is the cooling fans. Without air flow over the radiator the coolant does not lower in temperature before going back into the engine. When you are driving the air flow is steady, but when you idle (or reach a certain temperature) the cooling fans must kick on to help. For more help with testing and repairing the fans, contact our service department to schedule an appointment.

ANSWER : Hi there. Anytime the coolant system is worked on, a professional mechanic should verify the service steps with the manufacturer’s service guide. This will help them determine the right steps to complete the coolant bleeding – if it’s mandated by the individual manufacturer. It’s also a standard operating procedure for a mechanic to drain the coolant anytime replacing coolant system components; such as thermostat or coolant lines.

The radiator cooling fan relay is not one of those items that generally requires the fluid to be fully drained, but some mechanics will flush the radiator as a preventive maintenance service.

If you need to have further help having this checked, a certified technician from YourMechanic can come to your location to pinpoint any faults in the system.