I have an '02 silverado with the 4.8l engine and I am getting a P0332 code "knock sensor signal frequency outside normal range". I have cleared it several times but it comes back withing a few minutes. Does this mean the sensor is bad or is it telling me the engine is knocking? The sensor is under the intake manifold so it is a faily big job to replace it. What else should I look at? Thanks for any help.
It tends to suggest it is bad. GM in their wisdom moved it from a easily accessable location that was externally mounted with a SB series motors to the internally mounted one used with the new modular motors (4.8, 5.3 and 6.0)
----------------- TheSnoMan.com
The knock sensor is under the intake manifold? That's a brilliant design. Crap, I hope mine never gives me issues. Hopefully the ABS module isn't in the oil pan!
The theory behind this supposidly in that in the valve lifter galley it is closer to the heads and can "hear" better but if that it where they wanted to put it they could have compromised with a design that did not require you to remove the intake to change the sensor.
----------------- TheSnoMan.com
Augustus wrote
There are actually two sensors. It's not as bad to get at as you might think. And if they are more accurate in that location, you have to weigh the pro's against the con's. I know that in the
8 years that this design of engine has been out, we haven't replaced very many knock sensors on these engines.Ian
Are there other things I should look into before I attempt to change the sensors? Thanks
"mark" wrote
There were some issues with leaking intake manifold gaskets on these engines (not coolant, as they are not a wet manifold, but a vacuum leak). So if you are going to have the intake manifold off anyway, you could install the updated manifold gaskets.
Here is the updated gasket number from the GM bulletin.
"Replace the upper intake manifold gaskets with the teal green gasket material, P/N 89017589."
Ian
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.