Hello everyone,

I bought a 04 350z last week. I figured I should change all the fluids just to be safe. It turned out to be a bad idea because I'm having problems with random overheating.

I brought my Z to a shop for a coolant change. They replaced the coolant but ended up snapping the neck on the radiator. They ordered a new one (no charge) and installed it the next day. They had trouble burping all the air out of system because I drove only a few blocks and it the temp gauge was rising fast. I went back and they were finally able to get all the air out of the system.

Today is the third day and I've already notice a few issues
-The car has been a little below half on the temp gauge ever since I got it back from the shop. But when I was driving earlier today, I notice it was rising. I stopped the car for 5 minutes and started driving again. It was back to the normal temperature and stayed there.
-There is a tiny leak where the hose connecting the radiator and reservoir (attaches to the radiator).

What can be the cause of the temp gauge randomly rising and the problem going away after 5min of the car being off? I opened the radiator cap (when it was cold) and notice it's not filled to the top but the reservoir tank is 1/2 full. Does the radiator need to be filled to the neck?

What's the normal operating temperature? Right now, it's a little under halfway on the temp gauge.

 

The thermostat might be damaged. I have seen them get rusty and "randomly" close on you and causing overheating. You may want to remove the thermostat and or swap it out with a factory one or nismo if you want.

Generally the radiator is filled to the neck with fluid. The reservoir to rad hose is cheap and if its leaking you should swap it out.

Also make sure the temp sensor is not damaged, that could throw off the value of the coolant temp. That used to happen in my old Altima.

GL

P.S: I would start doing my own work on the car if you are mechanically inclined. Just my $.02c