Skip the auto shop - Our mechanics make house calls

Q: Throttle body position sensor

asked by on

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Air bag warning light flashes

Hello. When the airbag system warning light flashes and stays on, it means that an airbag system component has failed. When this happens the airbag system will become disabled and the airbags will not deploy if the car is in...

Q: The emergency brake is not working and multiple brake lights are on

The OBD-II error code P-0501 is a generic code that indicates an issue with the transmission speed sensor. This component is vital in the operation of the ABS and traction control system, which is probably why the light is illuminated....

Q: Diagnostic code P0411

A code P0411 indicates a secondary air injection system incorrect flow has been detected. This is essentially a system of flushing clean and fresh air into the exhaust system in order to keep the catalytic converter working at its best....

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...