i have a 2007 chevy Tahoe that recently had a check engine code p0121 throttle body position sensor. The vehicle would rumble when deceleration or braking between 30 and 10 mph. I changed pedal position sensor and throttle body position sensor and still getting that rumble. It less frequent but it is still occurring. Your thoughts??
My car has 170000 miles.
My car has an automatic transmission.
The rumbling noise may be coming from the loose catalyst in the exhaust piping. It would need to be verified by a road test to listen to the noise. If the catalyst is breaking up in the exhaust then the catalyst would need to be replaced. Another possible cause is a vibration from the cooling fan.
If you can duplicate the noise by revving and letting off the gas then you may be able to isolate the noise and the failure. Either the fan clutch or the exhaust catalyst will be at fault.
If you need help with these checks, consider YourMechanic, as one of our mobile technicians can come to your home or office to diagnose the rumble firsthand for an accurate repair.