My 2000 Maxima is still overheating after replacing the radiator, water pump, and thermostat. We have flushed the radiator and hoses and belched the coolant lines. Everytime we finish one of these attempts, I take it up the road and at almost the exact same spot the heater goes out and like clock work the engine starts overheating about 1 min later. I'm really hoping someone can give me an inexpensive solution. I bought a water control valve aka "heater control valve" aka "secondary thermostat", depending on what you're reading, to see if that will remedy the problem. Next step is temp sensor. I'm very much a beginner to this stuff so any advice would be greatly appreciated.

 

for starters are you missing coolant?

 

Junk thermostat is a possibly. Crap right out of the box sometimes. Front temp sensor is for the gauge and rear is for the ECU. I recommend Oem only for all three if needed.

Did you belch the car on an incline with engine running and heater on?
I saw you said you belched it, but just make sure you do it right. Nissan is picky IMO.

 

do you smell any coolant at all?

 

Turn on the AC and make sure that both fans are running

 

Yes, I have gone through about 3 gallons of coolant making sure it's at the right level while changing all these parts.

 

Is the bottom radiator hose collapsing? I know it is an issue on some cars, if the bottom hose is missing a re-enforcing spring since, the suction from the water pump causes it to collapse and restrict flow through the engine.

 

I did belch it on an "incline". I'm not exactly sure if I'm doing it right or if my incline is incline enough. I did it in my yard in a spot with a slight hill. I took the radiator cap off and placed a tall funnel over the radiator hole to allow coolant to rise in and air to escape. Any other ideas on a better way to belch it?

 

I smell it under the hood, but I have spilled some during all this. I don't smell any inside the car when it's running.

 

How can I tell if that's happening? Just get under the car while it's running and look for it to suck in?

 

Is your oil milky looking?