stlouisSteve
Junior Member
After initial start up and engine warm up, I hear a very low-pitched intermittent sound from the muffler. It's like a thumping bass sound, even when the audio/radio is off. If it wasn't a diesel, I would think it is a "backfire" . It occurs at idle and acceleration on city streets. It does not appear to persist on the highway at those speeds. Does anyone have input on this. It must have something to do with the engine being diesel, but I don't know if it is related to the DEF injector system. I have sinced learned the 2022 RAM has a feature called active noise cancellation, which cannot be turned off, according to the owner manual. Can it be adjusted? And I have six microphone sensors in the cab: two forward, two on front seats over the windows, and two in the rear. All in the headliner. Could active noise cancellation be the cause of the low pitched, thumping sound I hear? I know the cancellation can be disabled only by rolling down the front windows. This seems pointless.
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