hello all,

I have a little issue with my 2008 G37s. A while ago I noticed that my engine was getting warmer when stopped, and getting back to normal while driving. I checked both fans and were running fine.

Unfortunately, this blew up my head gasket, and after some costly repair, I got my G back yesterday. Once again, I noticed that the engine is getting warmer while stopping, and directly highlighted this to my mechanic. He said, its not an issue and you can expect the car to run a bit warmer after head gasket replacement. Naturally i am not convinced of this, but I am out of options on what can cause this. I even had the water pump replaced while changing the head gasket.

Can it be a semi clogged radiator?

I appreciate your advice guys, I am so worried of driving my car now.

Thanks!

 

Thermostat

 

^This.

In the event of a blown head gasket you should do a full over-look of your coolant system. More times than not, its the Thermostat going bad and getting stuck that is your issue.

Also, your car will naturally get hotter while idling at a dead stop. Your fans will help bring air through the radiator, however you're still going to increase temps to some degree until your thermostat opens up to relieve the heat. Its not until around ~3,500RPM that cars will manually open the thermostat due to high engine load.

I would have also had them take a look at the heads to make sure they're still level, unless it was part of their procedure.

 

Thanks guys for the suggestions.

I was testing the car today, and noticed that the radiator fan doesnt turn on unless I turn on the AC.
So I tried turning off the AC and waited a few minutes, but my car started to overheat without the fan kicking in.

Once I turned the AC on, both fans kicked in.

What can be the issue? is it the temp sensor ?

I bought a new thermostat and coolant sensor, and will have them both replaced. Hopefully this will fix the issue. Otherwise It will have to be the relays no?

 

Still thermostat

 

But it doesnt make sense, why wont the fan run if the thermostat is broken?

Anyway I ran the Auto Active test and the both fans ran on low and Hi speed. When I checked in the manual, this is what was written:

Cooling fan does not operate Perform auto active test.
Does the cooling fan operate?
YES
• ECM signal input circuit
• CAN communication signal between ECM and IPDM E/R

What does that mean exactly?

 

Check wiring harness connections between the ECM and the IPDM

Follow the troubleshooting steps in the FSM

It tells you what to do

Telcoman

 

Do you know where in the FSM I can find the troubleshooting? I checked EC-481 and that is mainly if the Auto active test is not normal. In my case the auto active test was normal.

Moreover, and it might be related, the lights on my my climate control dashboard are not working. The buttons are functioning but the lights are not.

 

Try here

Factory Service Manuals - NICO Club

Telcoman

 

Nice^^^^

 

I was checking there, but where do I find which troubleshooting I should use?

I changed the temperature sensor today with no luck. Fan still not working.