I bought a 2006 G35x when I bought it the guy told me the temp and gas gauge doesn't work. The gas gauge im not to worried about at the moment because I top off the car every 3 to 4 days and don't travel far. So for the temp gauge the needle moves barely when I crank the car but stays below the C. So about a week after owning the car I decided to change the temp sensor right behind the engine to see if that would fix the issue and it did not. Was wondering what everyone thoughts on this is. Is it possible my thermostat could be stuck open?? The cooling fans still come on and the car doesn't seem to be overheating or anything so that's a plus would just like to resolve this small issue...

 

Take an IR thermometer and see how hot the thermostat housing is while the engine is both cold and hot. I bet it's plenty hot (165+F) and that the issue is probably your instrument cluster failing.

If your engine was actually not getting hot you would throw code P0128 meaning the engine isn't warming up properly. This makes me think that the sensor is working correctly but the data sent via CANBUS is being interpreted wrongly by the cluster. Since you have multiple symptoms of a instrument cluster failure that's LIKELY the culprit but you need to troubleshoot it.

There are steps in the FSM to measure resistance on the temp sensor. Section EC - Engine Controls under DTC P0128 (page 247 for V35 cars). I would leave the sensor installed in the car, check it while the engine is cold and it should be around 2.5 ohms (make sure a non-auto range meter is set to the 20 ohm mark), with the engine at operating temp after you have driven it the reading should be around 0.25 ohms.

Troubleshoot the fuel sensor by removing the rear seat (couple of plastic rings you pull forward right below the seat cushion then lift the front of the seat straight up and pull forward, takes 10 seconds to remove the rear seat cushion). Next unplug the fuel pump harness and follow the steps in section DI - Driver Information (page 19 for V35 cars) to verify that the resistance reading (ohms, the horseshoe shape set your meter range on like 200 if it's not an autometer) matches about what it shows in the FSM. You will want to check with the tank full and "empty" or whenever you normally fill up, this makes sure that the resistance reading does actually change from 40-0 or 80-0 depending on which circuit you are reading. Super easy check.

Recommend using an angle head pair of needle nose pliers to disconnect the harnesses, much easier to hold down the release notch with them so you can use the other hand to wiggle the harness loose. This way you don't break anything.

Link to the FSM hosted by Nicoclub, strongly recommend you download each section for your specific vehicle and store it on your PC or phone, if you have a gmail account also store it on www.drive.google.com since your account has free cloud drive backup so you will always have it. Sometimes NNA likes to harass Nico and threaten them with legalities if they don't remove the FSM's.

https://www.nicoclub.com/infiniti-service-manuals

 

Thank you for the information this Wednesday im going to have my mechanic take a look at it and ill let you know what he says.

 

So when I turn my key I see the gauges jump just don't go up any further. If my cluster was out that wouldn't be moving at all. The mechanic wasn't able to look at it today because they were busy.