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Do knock sensors wear out?

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Old 12-15-2018, 01:36 AM
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Michael Benno
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Default Do knock sensors wear out?

I am in the midst of my intake refresh and after inspecting my knock sensors and can see no age or defects. I know they were replaced in 2010 (5K miles). My understanding in the few google searches I couldn’t find info about wear other than failure from broken wires. But I have no idea.

These look brand new.




Last edited by Michael Benno; 12-15-2018 at 02:56 AM.
Old 12-15-2018, 02:12 AM
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928 at last
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To the best of my knowledge, they don't "wear out". They cook in the oven until the wiring gives up the ghost....
But, for the price, why take the chance? Now you're in there, replace and put those ones in the "Parts Bin" for spares.
Old 12-15-2018, 02:44 AM
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worf928
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Originally Posted by Michael Benno
I am in the midst of my intake refresh and after inspecting my knock sensors and can see no age or defects. I know they were replaced in 2010 (5K miles). My understanding in the few google searches I did suggest that they don't wear out unless the wires are broken. But I have no idea.

These look brand new.
How “good” at taking out your intake to you want to get?

At 8-9 years old, those things are about 2/3s of the way through the expected life of the harness covering.

If you’re sure you will pull the intake again in the next five years, then leave them.

Old 12-15-2018, 05:19 AM
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FredR
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I reckon the knock sensors are good for 15 years of service and at some point after that the end connectors crumble as mine did a couple of years ago. They still carried on working [as indicated by my ST2 kit] after a bit of fettling with some RTV and I replaced them last winter with new items. If the connectors look in good nick I would leave them but then I have no reservations about pulling the inlet manifold that I have done for various reasons/projects.

My experience may not be typical given the hot climate I live in but I get the impression that what I see and have to deal with is often reported on this list with similar experience.

Bottom line in your position I would retain use of those items given you know the history unless you want to walk away from the job knowing you will not have to go in for another 15 years in which case replace everything under the lid as it were but that can get rather costly.



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