Q: Cel code p0129

asked by on May 14, 2016

I'm having an issue with my 2004 dodge ram 2500 5.7 hemi. I'm getting the cel code p0129. This is causing the truck to rough idle at times and stall when turning or coming to a stop. When I get the code and the check engine light comes on the etc light also comes on. The truck drives and idles fine other than it won't shift into 4th when the etc light is on. I've already changes the throttle body the map sensor the iat sensor the crankshaft position sensor and the pcv valve. I'm at a loss on what is causing the problem and what the fix is. Any help would be greatly appreciated. Thanks in advance

My car has 100000 miles.
My car has an automatic transmission.

Well you replaced all the parts associated with your code. You need a voltage meter to measure the voltage at the sensor. There should be a 5-volt signal and a ground on the outer wires on the sensor. If you do not have 5 volts, you likely have a wiring problem or a blown engine computer.

Use a digital voltmeter and verify voltage at the outer pins. The middle wire should read voltage as well. The most common problems include the sensor, wiring, or computer. Replacing the computer requires programming. If you still need assistance with this, a professional technician from YourMechanic can come visit your car’s location to diagnose the Check Engine Light for you. By looking at the car in person, they’ll be able to pinpoint exactly what the car needs and suggest the correct repairs.

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