2006 nissan pathfinder SE is overheating. I’ve replaced the radiator and thermostat still over heating. However, when I drive te

ANSWER : Hi there. It’s quite possible that you either have an obstruction in the coolant system (perhaps the heater core if your heater is also not functioning correctly), or you have air bubbles trapped inside the coolant lines. The best way to determine the precise source of your issue is to have a professional mobile mechanic come to your location and complete a car is overheating inspection.

ANSWER : The heater not working in some cases may be related to the overheating problem you are also having. This may be due to a faulty heater blower motor or potentially a bad heater core. As you may know, the heater core is a small radiator like unit that circulates the hot coolant from the engine through the heater core which then uses this warm coolant to heat the inside of the car with the help of the blower motor that blows the warm air through the vents inside the car. When the cooling system is not properly circulating coolant through the motor, this results in the warm coolant not being pumped through the heater core properly in order to warm the inside of the vehicle.

Engine overheating can be caused by a number of things such as low coolant levels, a faulty thermostat, or a failing coolant fan switch. As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds. When this switch is not working properly, this can cause the fans to come on intermittently, all the time or sometimes not at all. When this happens you will notice a temperature spike and drop occasionally as the fan comes on and off. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. As mentioned above, this also restricts the warm coolant from flowing through the heater core which uses this to blow warm air into the cab of the vehicle. I would suggest having an expert from Your Mechanic come to your home to diagnose your cooling system.

ANSWER : The complete cooling system should be drained and fresh clean water put in with a good quality radiator flush put in. Run the engine for at least 30 minutes at 1000 rpms with the heater in the on position but on lowest blower position. Once ran then check to see if both of the heater hoses are warm. This indicates a good flow through heater core. Now let engine cool and drain and refill with fresh water again and start and run a few minutes then drain system, install a new thermostat and refill with 50/50 new coolant designed for the vehicle. Run and check the engine comes up to operating temperature and heater output is hot once engine warms up. You will not get good engine heat if engine does not heat up.

ANSWER : Hi – sounds like you may have multiple problems with your engine cooling and passenger heating systems. It is possible that the cooling system has not been bled properly, and there is a large pocket of air in the engine/heater core; which would cause both overheating, and no passenger heat. Thoroughly bleeding the cooling system with the heater running full blast is the only way to correct this. A failure of the heater control valve, which allows hot engine coolant into the heater core for passenger heat, would cause some of these problems as well. I would recommend an overheating cooling system inspection 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.

ANSWER : It is likely your engine has a blown head-gasket, worn out water pump or somehow has a huge air bubble inside the engine that needs to be bled. The drop in engine temperature while on the freeway is actually a good sign – it indicates your radiator is getting good coolant flow, and the radiator is doing its job, transferring heat out of the engines cooling system. A YourMechanic certified technician can come to your location to perform a Car is overheating Inspection on your vehicle and help you diagnose and repair this issue.

ANSWER : Hi. It sounds like the heater core is clogged and restricting the flow of coolant in the coolant system. There is also the possibility that the new radiator is defective and is causing the car to overheat. The head gasket could also be blown. Just because the antifreeze has not mixed with the oil doesn’t mean the head gasket is not leaking and is causing the Jeep to overheat. If you need to have this scoped out by an expert, a certified professional from YourMechanic can come to your location to diagnose the overheating problem and have this issue corrected.

ANSWER : I’m sorry to hear about your overheating issues. There are a few possibilities that can cause an engine to overheat. The radiator, water pump, and thermostat are definite possibilities, but there are a few others that are possible also. A faulty cooling fan is the first thing that comes to mind, but it could also be a head gasket issue, clogged coolant passages inside the engine, or faulty radiator hoses. I would first look at the cooling fan and/or the cooling fan switch. It would be necessary to start with a cold engine and check to see if the fan comes on as the engine warms up. Most of the time, you can do a quick check by turning on the air conditioning, as this should signal the fan on also. If this is something you feel you could use a hand in diagnosing/repairing, contact a certified mechanic, like the mobile mechanics at YourMechanic.com.

ANSWER : Hello, thank you for writing in. Overheating issues are very frustrating. When in this situation, you will want to go ahead and test the radiator cap and make sure it is regulating pressure correctly. Secondly, the water pump needs to be tested or replaced. Although it may seem like it is working, it may not be pumping enough coolant through the system to keep up with heat transfer needed. You may also want to check the oil and make sure it is in good condition, as the oil plays a large role in regulating engine temperature as well. For more help with diagnostics, contact our service department to schedule an appointment.