I hooked up the scan tool today, and it showed two codes, Knock Sensor 1&2 Circuit Low Frequency. How am i supposed to fix this? What could cause this?
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I hooked up the scan tool today, and it showed two codes, Knock Sensor 1&2 Circuit Low Frequency. How am i supposed to fix this? What could cause this?
It's pretty common for these knock sensors to get messed up from moisture.
I would remove the intake manifold, replace the knock sensors and small harness.
Only way to do it.
yup...i had to do that about 3 months ago
Yep. Two sensors, one harness (if brittle), intake gaskets (if the old style or high miles), remove the dams from the intake, and seal the FRONT HALVES of the valley grommets with silicone.
its easy,just replaced some on my 03'yukon and buddys 02'2500 hd last week.1 1/2 hour job
remove intake,get ready to clean up a mess under there too.cover the cyl head ports before you clean it.and yes when you install the new ones,put some silicone around the seals that cover the sensors.
what do the Knock Sensor do?
can u delete knock sensors like the 02's??lol probably dumb question.
what would happen if they go bad?
well when my were bad,it didnt have any power at all.it wouldnt even spin the tires if held the brake and gas.u can feel the power held back too.
most hated,u from the rgv?
Depends on what year, etc. what the PCM does when there are current KS codes. I know of at least one guy with his deleted but he does his own tuning. For a DD running pump gas I'd fix them of course. They actually work sort of like a microphone. When they get corroded they do not respond to the onboard tests the PCM performs. The DTC will then set and the PCM will ignore them staying in safe mode.
BTW, only seal the front (half moon) of the boots on the harness to make a dam that forces water around them instead of into them (the engine slopes downhill slightly towards the rear).
i think thats whatz wrong with mine. cause i can have my gas all the way to the floor and it wount spin,at all
is your ses light on??more than likely yea thats the problem.
no SES light though
oh damm,well my ses lite would come and go and that was the problem.
So knock sensors retard spark timing? Without that, the power goes downhill. I need to fix that then. How much are the knock sensors (Please don't tell me they are as expensive as O2's :( )
42.99 at autozone.
I had knock codes, then they magically stopped. Truck sat for a few months though.
So should i wait a little while, or go ahead and replace them?