Q: I have a 2007 dodge charger v6 3.5L engine NAG1 RWD Transmission. I'm confused in what is causing limp mode in my car..when the c

asked by on March 19, 2017

I have a 2007 dodge charger v6 3.5L engine NAG1 RWD Transmission...I'm confused in what is causing limp mode in my car..when the codes are cleared initially I can drive a day or two then the first and only code I'm getting is p0420 bank 1 cat efficiency below threshold..It doesnt go in limp mode still and I can drive another day or two..Eventually it goes in limp mode and then I receive the codes p2767 and p2784..input speed sensor codes..The transmission shop recommends changing the conductor plate..I've already replaced the catalytic converter on my driver side and bank 1 o2sensors but I'm still getting the po420 code for bank1.I'm trying to find out if the po420 code could be causing limp mode or if it's just the p2767/p2784 codes.The trans shop is saying the p0420 code has nothing to do with the limp mode, the limp mode prob can only be diagnosed after it goes in limp mode and that's y I'm only getting the sensor codes after and not before.Don't wanna get a new plate and still limp

My car has 119505 miles.
My car has an automatic transmission.

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The code P0420 will cause the computer to put the transmission in limp mode to protect the catalytic converter. Check the following areas to see the cause for the P0420 code condition:

P0420

  • A damaged or failed oxygen sensor
  • The oxygen sensor wiring damaged or connected improperly
  • The engine coolant temperature sensor is not working properly
  • A leaking exhaust manifold or a leak in the exhaust system
  • The spark timing is retarded
  • There is a leaking fuel injector or there is high fuel pressure
  • The engine has a cylinder misfire
  • The engine oil is contaminated

For the codes P2767 and P2784 are related to the input speed on the torque converter. The transmission will default to a limp mode if the torque converter is causing the input shaft to have a loss of speed. If you need further assistance with your check engine light, then seek out a professional, such as one from Your Mechanic, to help you.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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