Im new to this forum and Im an owner of a frustrating 01 Qx4. The Problem is that my temp gauge is going up and down. I have checked my coolant fluids and seem to be good, I have replaced the thermostat and even replaced the water pump which was a pain in the a**. The problem is still there. Could it be the ECT sensor? I was told by the person at autozone that this could be it cause of the service engine soon light being on. Im too afraid to drive it cause its my only ride and would hate to f-up the engine. If it is the ECT where the hell is it. Whats frustrating this car only has 86000 miles on it.

BTW I have posted the thermostat and the pump on craigslist on Dallas, Tx

jg’scutie wrote:I was told by the person at autozone that this could be it cause of the service engine soon light being on.

Did the guy offer to read the code for you?That's the next thing I'd do. Get a code and post it here. It can't hurt.

The code is P0217.

JG

The P0217 code is extremely generic. This is a problem because it really only tells you that the coolant (at some point) became hotter than it should have. Pretty much the only thing you can do is try to troubleshoot your entire cooling system. I am sure you've done a full flush, but have you physically flushed the radiator? You should remove the top/bottom hoses from the radiator and flush it thoroughly with a really strong stream of water. Also, is your fan clutch operating properly? Try to spin the clutch with your hand with the vehicle off, it should only spin 4-5 times. If it spins less or more than you likely have a bad clutch. Also, one very important thing to check is if you are building pressure in the cooling system. Have you done a pressure check of your entire cooling system to ensure you don't have a leaky head gasket or a cracked block or head? If the cooling system is building up excessive pressure, then this is often a sign of cylinder pressure entering the cooling system. The ECT sensor is also a culprit for the excessive reading, you can test the sensor using a multimeter and a boiling pot of water. The full test procedure is in the FSM for your vehicle ( http://www.nicoclub.com/FSM/QX...m.pdf , start on page EC-314). The ECT sensor is located between the rear of the engine and the firewall and it will be extremely difficult to get to.

Thanks bro I just fully flushed the radiator like you said. Took the top and lower hoses off and ran the water hose with some pressure. Filled it up with new coolant and Im good to go. Temp gauge stays in the middle after driving for a while. Like I said thanks again. JG