Novak Conversions Jeep Wrangler TJ radiator

Nagging P0128 code

Thor

TJ Enthusiast
Original poster
Supporting Member
Joined
Nov 20, 2019
Messages
232
Location
Central Florida
Been dealing with P0128 code for awhile. I replaced the thermostat and coolant temp sensor and it’s still throwing the code. The jeep gets up to operating temp just fine and stays at proper temp. Never overheats. Coolant level is where it should be. I did see where another issue for this code could be the air intake temp sensor but there is no P0113 code. Below are two pictures of the sensor. The first picture(dirty side) is the air filter side. The second side(clean side) is the throttle body side. Should I look into cleaning the sensor and if yes, how? Or should I look into replacing the sensor? Any and all input is appreciated bc I am at a loss right now. Thank y’all.
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You’re going to have to look at live data to see what the computer is seeing. Then with the sensor unplugged, check for your 5v feed and a 5v bias on the signal wire. Then you can install a resistor or variable resistor and play with it while watching live data to be sure the wiring can carry the signal to the PCM, and that the PCM can interpret the data.

If your live data shows -40, you either have a bad sensor, or a break in a wire.
 
Novak Conversions Jeep Wrangler TJ radiator