My 2003 G35 Sedan began overheating a few days ago. And it happens all the time, probably after 5 minutes of use.

I took my car to a local (and reputable) mechanic shop (Infiniti Master Techs) for an oil change and inquired about the overheating issue.

As soon as the car was on the lift, the mechanic said something along the lines of "the car is cold at the bottom. Some of the hoses are not warm." Not really sure what that means, but he then proceeded to tell me it could be the thermostat. Note that this wasn't a thorough check, I simply just asked him to do a visual check.

As I drive back home, the car once again starts to overheat a few minutes into my drive. Fast forward back home, I can here some weird noises going on under the hood as soon as I turn the car off.

I pop the hood, and can here a purging sound (the sound you'd here when you're getting water from your water dispenser with the 5 gallon jug on top). I can also see bubbles rising to the top on the coolant reservoir tank. And I can here a 'dripping' sound coming from the engine bay as well, but no coolant is spilling or dripping down to the floor (no visible signs of a leak).

Based on the symptoms described, what can the source of the problem be?

The fan seems to be running, although I wouldn't know if its running properly or not. This is my only vehicle so I need a fix asap. :52:

 

thermostat, air, cooling fan, sensor, etc.

what's the code? P1217?

 

Not sure about the code. I haven't noticed any check engine light.

 

really? is it painted over or something? how bout you check anyway?

what're you in limp mode?

 

This is a standard check for thermostat problems. Thermostat stuck closed. Coolant does NOT flow from motor to radiator because it is blocked by the thermostat.

 

It is probably a thermostat. I hope you aren't driving around with the temp gauge pegged and the car overheating. The thermostat is fairly cheap and easy to replace.

 

Standard check as in typical thermostat symptom/problem? So it's safe to say it's most likely a thermostat problem?

Not at all. As soon as it hits 3/4 of the way up I pull over. It started a few days ago so I've been forced to pull over a few times and practically walk home with the car. Luckily it's all been very short distances.

 

Probably a thermostat, but it could be air in the system, too. These are very particular about purging to get the air out.
I think it's much more common to have a T stat fail open, but unfortunately they can fail closed. Run your heat full blast for a ghetto temporary solution so it can at least exchange some heat there, but better get it fixed.

 

Most likely suspect yes. But it may be:

Water pump
Inoperative cooling fan

NOTE: Insufficient cooling can be dangerous. You have no oil temperature gage so it is impossible to know what is happening inside the motor. Get the car fixed now.

 

Headgasket