air temp sensor
air temp sensor
i've searched for the answer to this question but i've come up empty handed, so i'll give you a shot. when i bought my car (95' 240sx) the check engine light was on, they told me it was the front o2 sensor so i got it replaced but the light was still on. i went to my local nissan dealer about this and they said it was becasue when the original owner put a air filter on and took off the air box he never replaced the air temp sensor. they said i could bypass the sensor by sticking a piece of wire into the end of the connector. i tried this but no luck so im asking if there is any way to bypass this without buying the temp sensor.
My guess: Probably needs a resistor. I would think the resistance of the sensor would never be 0 or infinity, and a wire or unhooked will give these values, which the ECU is probably programmed to flag codes for. You need to know the resistance of the sensor at the temp you're running in. But the car won't run quite as well as it would with the sensor in place, except at the temp you select the resistor for. It'll run leaner when cold and richer when warm.
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
You could use a potentiometer [volume control] of around 5,000-10,000 ohms and set the resistance [make a calibrated dial] for the temps you want to report to ecu.
Easier to get the sensor from junk yard.
OBD1 just checks for open and short at start up [if sensor is returning 0 volts or 5 volts [short] then it throws a code and runs in fail safe mode.
Easier to get the sensor from junk yard.
OBD1 just checks for open and short at start up [if sensor is returning 0 volts or 5 volts [short] then it throws a code and runs in fail safe mode.
The temperature sensing unit employs a thermistor which is sensetive to change in temp. Electrical resistance of the thermistor decrease in response to the temperature rise. This sensor is not directly used to control the engine system. It is used only for the on-board diagnosis.
This sensor has 2 possible failures it can detect 1] open or short (your failure) 2] the other is rationality, if the incorrect voltage is sent to the ecm as compared to the engine coolant temp it will through the code P0110. your resistance on it at 68 degrees would be between 2.1k - 2.9k ohms at 122 degrees it would be 680 -1k ohms.
your best bet is to get one from a junk yard as dennis said.
This sensor has 2 possible failures it can detect 1] open or short (your failure) 2] the other is rationality, if the incorrect voltage is sent to the ecm as compared to the engine coolant temp it will through the code P0110. your resistance on it at 68 degrees would be between 2.1k - 2.9k ohms at 122 degrees it would be 680 -1k ohms.
your best bet is to get one from a junk yard as dennis said.