Skip the auto shop - Our mechanics make house calls

Q: Knock Sensor issue

asked by on

I just bought a 2003 Chevy Silverado 1500 z71 4x4, 135,000 miles, 4.8L V8 with some rust, it does have a slight ruff idle and sounds like lifter knock when hot or cold, if i blip the throttle the knock go's away for a few mins, i changed the oil and spark plugs as soon as i got it home, the check engine light was on as well. i went to advanced auto and had them scan the code, it came up as knock sensor bank 2, i purchase 2 new knock sensors, wiring harness and intake gasket, installed everything and the code came back after a few days of driving it as bank 1 now, i traced the wires from the knock sensor harness and everything looks fine, i pulled them back out and replace them once again. but same thing, engine light came back after a few days. would replacing injectors or coil packs help me any?

My car has 135000 miles.
My car has an automatic transmission.

The sensors are doing their job and telling you there is a knock in the engine. Even though it may seem like the sound went away, you may not be able to hear it when you drive but the sensors can. The knock sensors are designed to produce a voltage when they hear a knock noise from the engine internal parts.

You need to have the noise you hear checked by a mechanic to see what is the cause and what needs to be done in order to fix it.

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

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: p0175

Hi There, This may not be as bad as it appears to be as these codes may all be related. Code P0175 relates to a rich fuel condition (too little oxygen in the exhaust) which may be caused by a...

Q: My 2006 Silverado truck seems to be burning oil is this an expensive fix?

Hi there. In most cases, when the engine burns oil or consumes oil every few weeks as you've described, it's caused by one of two things; valve guides that are worn out, or piston rings that are damaged. Both of...

Q: Car leak, ABS on, car too low warning

Hello. I would think that your strut has blown out an internal seal or a brake component such as a brake line has failed. I suggest to have a professional technician inspect the braking system and strut for leakage to...

Related articles

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...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.