Shutting off knock sensors???? Why?
12-07-2012, 07:31 PM
#21
the sensors ground thru the block on an LS1
one of 2 things...
either a bad sensor, or a bad signal wire...
pull the intake, check the wires for continuity with a multi-meter
do a visual inspection of the wires for cracks/breaks/burn spots/bare wire
if you have no signs of the wire being bad, replace the Sensor in question(the front one is bank one)..
if that doesnt solve it, then buy Knock sensor wire harness
both items can be gotten at a GM Dealership for reasonably cheap
I personally would Just do them both because its easier to only have to pull the intake once.
one of 2 things...
either a bad sensor, or a bad signal wire...
pull the intake, check the wires for continuity with a multi-meter
do a visual inspection of the wires for cracks/breaks/burn spots/bare wire
if you have no signs of the wire being bad, replace the Sensor in question(the front one is bank one)..
if that doesnt solve it, then buy Knock sensor wire harness
both items can be gotten at a GM Dealership for reasonably cheap
I personally would Just do them both because its easier to only have to pull the intake once.
12-07-2012, 07:35 PM
#22
you can do it all in one evening after work...
its really not all that hard to get the intake off.
take back whatever you dont use....
they usually have some sort of a no refund on installed electronics policy..
so look at teh wires first... if they look good... and test fine with a multi-meter, then just do the sensor and return the wires after you find out that the sensor did the trick.
12-09-2012, 03:23 PM
#24
I got the same codes I was going to ask about this happy I seen it look like ill be taking the intake back off and replacing both parta
12-09-2012, 03:26 PM
#25
which leads to them getting melted by engine heat..which makes them short out...
when you pull the intake off.. look closely at the wires...might be a simple wire splice fix
12-09-2012, 03:34 PM
#26
a common thing that happens, is people do an intake change...and when they put it back on, they pinch the wires....
which leads to them getting melted by engine heat..which makes them short out...
when you pull the intake off.. look closely at the wires...might be a simple wire splice fix
which leads to them getting melted by engine heat..which makes them short out...
when you pull the intake off.. look closely at the wires...might be a simple wire splice fix
12-11-2012, 09:04 PM
#27
again... read my post.....
there are no reasons to turn off knock sensors...
you just need to learn how to tune the settings for them.
headers resting on the block, wont cause knock...its not even the same frequency that the knock sensors are looking for.
LS1 sensors look for an 11.1 kHz sound, and look for a certain amplitude...
LS3 style sensors look for a lower frequency around 5k ish...
in both cases, you can add a simple bandpass filter to the signal wire if you understand a little about electronics...which will remove almost all problems with false knock casued by other noises.
there are no reasons to turn off knock sensors...
you just need to learn how to tune the settings for them.
headers resting on the block, wont cause knock...its not even the same frequency that the knock sensors are looking for.
LS1 sensors look for an 11.1 kHz sound, and look for a certain amplitude...
LS3 style sensors look for a lower frequency around 5k ish...
in both cases, you can add a simple bandpass filter to the signal wire if you understand a little about electronics...which will remove almost all problems with false knock casued by other noises.
I said that people do for those reasons
I've seen a car pull timing on the dyno because of headers hitting the block, Whatever frequency the sensors detect, they were obviously making it
12-12-2012, 01:09 AM
#28
they just made enough noise to be so loud it triggered the knock sensors because they were not tuned properly to match the system in use with the mods in use
the knock sensors are centered around a frequency... but the filtering is non existent, so they pick up everything...and other noises can be loud enough to trigger them at their stock default values
03-23-2013, 04:14 PM
#29
incorrect.....
people Just dont know how to fine tune knock sensitivity so they do it the easiest way possible, which is to turn them off..
most people also dont know how to tell the difference between real knock and tip in knock(which is calculated...not heard by the sensors)
I run a 252/274 cam with knock sensors and no issues.
also running a Motor plate and mid plate with a Poly trans mount...
I never had any issues with my sold motor mounts before I did the motor plate and mid plate
if somebody tells you that you cant use knock sensors with a certain combo... its because they dont know how to tune them to work with that combo.
people Just dont know how to fine tune knock sensitivity so they do it the easiest way possible, which is to turn them off..
most people also dont know how to tell the difference between real knock and tip in knock(which is calculated...not heard by the sensors)
I run a 252/274 cam with knock sensors and no issues.
also running a Motor plate and mid plate with a Poly trans mount...
I never had any issues with my sold motor mounts before I did the motor plate and mid plate
if somebody tells you that you cant use knock sensors with a certain combo... its because they dont know how to tune them to work with that combo.
Can you explain how to tune the knock sensors?
03-27-2013, 03:46 PM
#30
There is no such thing as "predetonation".
There are many people who use the term, but the fact is, there is no such thing.
Detonation and Pre-Ignition are forms of uncontrolled combustion.
I'm not just a person with an opinion, I do this stuff for a living. I have done combustion analysis for OEM calibrators.
07-01-2013, 09:56 PM
#33
Replaced the sensor and the harness. I still have an SES light. I'm going to check what codes they are again this week. But the SES has come on and gone back off after several shutdowns and startups. It always comes back on though when I am in off of the gas in gear and letting the engine rev itself down. Like when I'm slowing down for a light that I think is going to change soon so I downshift into 4th or if I'm cruising and come up to light traffic and let off of the gas. I want this SES light gone!
07-02-2013, 12:23 AM
#35
Replaced the sensor and the harness. I still have an SES light. I'm going to check what codes they are again this week. But the SES has come on and gone back off after several shutdowns and startups. It always comes back on though when I am in off of the gas in gear and letting the engine rev itself down. Like when I'm slowing down for a light that I think is going to change soon so I downshift into 4th or if I'm cruising and come up to light traffic and let off of the gas. I want this SES light gone!
Sorry for the
07-02-2013, 11:17 AM
#36
No problem dude! If you look back in the thread, you'll see where one of the guys recommended going to a dealer and buying them. That's what I did. I went and picked up an oil pressure sending unit, knock sensor and the harness. And I got all of the hoses and connectors to redo my PCV, that way I could do it all at once since I would have the intake Mani off. I don't remember how much it all was but yeah it was kind of expensive. But worth it if it fixes the problem in my book. SES lights are annoying as hell to me. Especially when they go off for a little while then come back.
07-07-2013, 09:10 PM
#38
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No problem dude! If you look back in the thread, you'll see where one of the guys recommended going to a dealer and buying them. That's what I did. I went and picked up an oil pressure sending unit, knock sensor and the harness. And I got all of the hoses and connectors to redo my PCV, that way I could do it all at once since I would have the intake Mani off. I don't remember how much it all was but yeah it was kind of expensive. But worth it if it fixes the problem in my book. SES lights are annoying as hell to me. Especially when they go off for a little while then come back.
