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Discussion Starter #1
Hoping someone can help me diagnose a real issue with my JK I have a 2013 Jeep Wrangler Unlimited Sahara which I bought used from the dealer had 35000 miles at the time (76000 now) a year after I got her the check engine light comes on I took her to the dealership to get a diagnosis turns out I had a bad knocker sensor bank 1 they replaced it $400 literally a year later to the date check engine light comes on just before re-registration turns out knocker sensor bank 1 by this time I was going to be different mechanic they assured me it was nothing serious because even though the sensor was tripped it was no longer reading as an ongoing problem he clear the code months will go by before engine light comes back on for the same reason but will clear up within a day or two, now all the sudden check engine light will come on every other day same reason knocker sensor bank 1 and will clear itself within a day I figured is my engine is truly knocking both sensor 1 and 2 would be tripped, tried different gas stations kept the tank full and always kept the same octane 87 and to make things a little bit more confusing no light on a 360 mile round trip from las Vegas to Zion Utah plus another a hundred miles on off-road Adventures but the day after I comeing home check engine light comes on, the only thing I can think of that would be different is the gas octane in Utah is 85 unlike Las Vegas 87. Would like to hear your opinions on this.
 

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First it's a Knock sensor not knocker.

There are only 2 codes for knock sensor. One for each sensor as there are 2 sensors. These codes are circuit codes and they are for validating the integrity of the circuit. Those codes don't trip for actual knock so changing gas or trying to get the engine not to knock won't help. Each knock wire has 2 wires. Looks like it might send 5v to the sensor and return something based on what the sensor senses. If the PCM sees over 4.8v or lower than .2v, then the code sets.

Likely it's another bad sensor or wiring is shorted to power or ground. It's possible it's a PCM but doubt it. Senor or wiring is the likely issue.
 

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First it's a Knock sensor not knocker.

There are only 2 codes for knock sensor. One for each sensor as there are 2 sensors. These codes are circuit codes and they are for validating the integrity of the circuit. Those codes don't trip for actual knock so changing gas or trying to get the engine not to knock won't help. Each knock wire has 2 wires. Looks like it might send 5v to the sensor and return something based on what the sensor senses. If the PCM sees over 4.8v or lower than .2v, then the code sets.

Likely it's another bad sensor or wiring is shorted to power or ground. It's possible it's a PCM but doubt it. Senor or wiring is the likely issue.
Incorrect. The knocker sensor lets you know when you drive past a chick with amazing knockers.
 

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Discussion Starter #4
Thanks for the proper pronunciation now how would I go about checking the wire connections do I need to remove the intake manifold?
 

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I'd actually test the sensor at one of the connectors without removing the intake. I think the large connector that sits to the left of the upper intake has the wires but can't confirm that where I am. Would have to check at the factory service manual at home.

I'd back probe the two wires at the connector and see what voltage you get. Look up wire back probing for instructions (not responsible for other google results you may get). You should get between .2 and 4.8v. You should be able to tap the engine block with a screwdriver handle and get the voltage to change. Would be better to view on a graphing multimeter or scope but DVOM may work.

Knock sensor 1 signal is Dark Blue/yellow stripe, Return is Brown/Light Green
Knock sensor 2 signal is Brown/white stripe, Return is white/brown stripe
 
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