Ambient Temperature Sensor Screwy

OldGuy

My outside temperature reading is slow to reach its final reading (about an hour) and is consistently about ten degrees low. I went to the dealer. He claims to have replaced the sensor. There is absolutely no difference. He is stumped. Could the sensor be partially blocked and only receiving a portion of the sunlight's temperature or outside temperature. Anyone else have this problem? Any suggestions?

MattP725

Ambient implies not affected by sunlight. I'd take it back. Only heard of too high via oil cooler locations.

mayday813

I note the same problem when leaving a cooler garage and driving outside into to near 100 degree temps. It takes the indicator at least five to ten miles of driving to register the correct temperature. When the outside temp is lower, the guage registers much more rapidly. I've got an '09 G-37 sedan that has the same issue. In reviewing other Nissan forums, this appears to be a common Nissan issue. Nissan apparently has logic built into the ECU that attempts to account for heat soaking of the sensor when the engine is hot. In addition, the vehicle has to be moving to register correctly.

Verticity

I'm having the same temperature sensor problem on my 40th Z. When the temperature drops, it seems to register almost immediately, but is incredibly slow to respond when the temperature rises.

I live in Colorado, where the temperature can swing 40ºF at the drop of a hat. Case in point, this morning it was 31ºF when I started the car and the display was accurate. By the time I got to work (10 miles), the temperature outside was 45º but the display said only 37º. A couple of hours later, I left to run an errand and it was 58º outside, but upon starting the car, it still said 37º and only rose to 48º by the time I reached my destination (8 miles). When I left there another hour later and drove another 15 miles, the outside temperature had reached 74º but the display only ever got to about 62º. After that, I parked it for several hours, then the temperature fell to 57º by the time I left work. When I got in the car to leave, it read accurately all the way home.

This is an incredibly annoying problem, particularly when the readout throws warnings about icy roads and it's actually ten or fifteen degrees too warm outside for any such possibility (not to mention that in Colorado, the road temp is almost always several degrees warmer than the air temp anyway).

Strangely, I never noticed this until about two months ago and now it seems to happen all the time. I'm not sure whether I was just oblivious to it previously or whether it has only started to malfunction recently. I should say that this summer, we had highs in the 90's and 100's frequently and the sensor read accurately even at those extremely hot temperatures, so I know it's capable of sensing the proper range and that it isn't permanently skewed by some constant or scalar multiple.

I contacted my local dealer about it. They seem to think I'm imagining the dysfunction and I don't know how to come up with a reliable way to prove my side given that it's virtually impossible to schedule an upcoming service visit that requires cooperation of Colorado weather.

Are there any concrete suggestions out there for what I should do? I don't know whether this is a substantiated limitation or whether I should seek to have the sensor replaced... Also, does anyone know whether the temperature displayed in the instrument cluster is factored into the ECU's air/fuel calculations or whether a different sensor is responsible for that?

Thanks in advance!

370Z Purist

I feel like Nissan puts way too much effort into their ambient temperature sensor.

Plus I feel that the ambient temp sensor is just a convenience thing. I know the temperature driving out, I don't need to be told it every moment of driving. Don't people check the weather so they don't drive their Z's through hail and snow? Or perhaps just a rainstorm?

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