Removing Knock Problems
05-14-2005, 07:13 PM
#1
Removing Knock Problems I have been trying to remove the KR on my girlfriends car for about 3 days. I have fixed it 5 times and I still get KR. What is the problem.
Yes I am writing the new files to the pcm so I am changing it. How many times did you guys have to go through and change the high octane table. Also this is a 100% stock car
Yes I am writing the new files to the pcm so I am changing it. How many times did you guys have to go through and change the high octane table. Also this is a 100% stock car
05-14-2005, 07:26 PM
#2
TECH Fanatic
iTrader: (11)
Join Date: Nov 2003
Location: Marysville, WA
Posts: 1,781
Likes: 0
Received 0 Likes
on
0 Posts
Is it also a 1998? If so, they are notorious for bad knock sensors. There was even a TSB on it. They used a different generation of knock sensors than the 1999+ F-bodies. I have intermittent KR on my 1998 with stock timing tables.
05-14-2005, 10:19 PM
#6
TECH Apprentice
Join Date: Jan 2002
Location: Princeton, IN
Posts: 364
Likes: 0
Received 0 Likes
on
0 Posts
I have the new style knock sensors
Ls6 valley cover
i have tried tr55 and tr6s
Sea foam, top engine cleaner many times...
98 have a lot of timing… but I’m not sure if this is the problem… burst knock? That seems to be my problem… how much timing is it pulling when it pulls timing? 26? 27? This it only at WOT or when the converter is locked up? 4th gear?
The only thing that has reduced mine is lower coolant temp. 170-180-f
Ls6 valley cover
i have tried tr55 and tr6s
Sea foam, top engine cleaner many times...
98 have a lot of timing… but I’m not sure if this is the problem… burst knock? That seems to be my problem… how much timing is it pulling when it pulls timing? 26? 27? This it only at WOT or when the converter is locked up? 4th gear?
The only thing that has reduced mine is lower coolant temp. 170-180-f
05-15-2005, 08:35 AM
#7
TECH Fanatic
iTrader: (11)
Join Date: Nov 2003
Location: Marysville, WA
Posts: 1,781
Likes: 0
Received 0 Likes
on
0 Posts
One of the first things people usually do is swap in the newer style knock sensors and wiring harness. This makes it a direct plug-in affair, but you'll have to search for the part numbers. GMpartsdirect.com has good prices on the stuff you will need.
Trending Topics
05-15-2005, 10:44 PM
#8
how hard is this going to be. I mean I installed my own cam and everything else on my car I just need to know how long it is going to take. All I should have to do is take off the intake right. Should not have to remove anything else. And the wiring harness how much of that am I going to have to change.
And when I call these guys and say I need Knock sensors do I need to say the newer style knock sensors or ask for a year......
And when I call these guys and say I need Knock sensors do I need to say the newer style knock sensors or ask for a year......
05-16-2005, 05:54 AM
#9
TECH Fanatic
iTrader: (11)
Join Date: Nov 2003
Location: Marysville, WA
Posts: 1,781
Likes: 0
Received 0 Likes
on
0 Posts
I haven't done this yet myself, but I'm pretty sure you just have to remove the intake, then the old knock sensors. The wiring harness should have a disconnect plug at the rear of the intake. You just swap in the new harness at that disconnect point and re-install everything.
05-16-2005, 10:02 AM
#10
TECH Apprentice
Join Date: Jan 2002
Location: Princeton, IN
Posts: 364
Likes: 0
Received 0 Likes
on
0 Posts
It’s not hard... Oh and you want to get 2002 knock sensors and knock harness.
Remove intake "hardest part" hour if you have done it before never done it? 3+ hours
Remove knock sensors
Unplug old harness/plug in new harness
install new sensors
Reinstall intake
Do not even try to do this with out an inch pound wrench, if you do not follow the intake TQ spec and bolt order your intake will leak.
And you’re done, but I don’t think it will fix your problem. It might help, but if you don’t have codes or have rusted out sensors then it might be a lost cause
One of my sensors had rusted badly but no water had got in side so they seemed to be fine… I swapped for new one anyway but at that point I was ready to try anything.
I think I had around $100 in two new sensors and harness… the harness is around $60 if I remember right and each knock sensors is around $30 “maybe less”
Take a look at the ls1 to ls6 intake swap on here www.ls1howto.com this will give you most of the steps you need.
here is another that might help
http://www.ls1howto.com/index.php?article=5
http://www.ls1howto.com/index.php?article=18
Remove intake "hardest part" hour if you have done it before never done it? 3+ hours
Remove knock sensors
Unplug old harness/plug in new harness
install new sensors
Reinstall intake
Do not even try to do this with out an inch pound wrench, if you do not follow the intake TQ spec and bolt order your intake will leak.
And you’re done, but I don’t think it will fix your problem. It might help, but if you don’t have codes or have rusted out sensors then it might be a lost cause
One of my sensors had rusted badly but no water had got in side so they seemed to be fine… I swapped for new one anyway but at that point I was ready to try anything.
I think I had around $100 in two new sensors and harness… the harness is around $60 if I remember right and each knock sensors is around $30 “maybe less”
Take a look at the ls1 to ls6 intake swap on here www.ls1howto.com this will give you most of the steps you need.
here is another that might help
http://www.ls1howto.com/index.php?article=5
http://www.ls1howto.com/index.php?article=18
05-16-2005, 01:37 PM
#12
TECH Apprentice
Join Date: Jan 2002
Location: Princeton, IN
Posts: 364
Likes: 0
Received 0 Likes
on
0 Posts
Because I did it and had no change in knock.
I know some sensors are bad but obd2 would pick up on this and set a code if you had a real bad problem with it.
You should do all the other easy thing 1st before you go tacking your intake off... it's kinda a shot in the dark thing.
yeah I did it but I tried things for years "I mean years before I tried knock sensors" I have an ls6 valley cover to and I did that at the same time... my AFR is a hair on the rich side so I’m not knocking because it's lean
I’m not knocking because I have oil in my intake.
I’m not knocking because I have an exhaust pipe banging on the floor pan
I’m not knocking because of low octane.
It’s not saying it’s not your sensors but I just think you should try to investigate other possibilities of the knock problem.
Any 98’s guys replace JUST their knock sensors and this fixed their knock problem? 100% no retarding of timing at part throttle and full throttle?
What is the max timing you see at WOT “before and after knock kicks in”
What rear? What rpm. Converter locked up? Part throttle knock? Gear/rpm, temp outside, coolant temp? What fuel table? What problem are you logging this what? If it’s autotap or efilive I can take a look at the logs
I could even post some of mine to compare…
These things are important in finding the source of the knock.
Is the car reducing timing at idle? Can you hear the detonation? I still have never heard my car detonate so I have always felt the problem was false knock or burst knock.
I know some sensors are bad but obd2 would pick up on this and set a code if you had a real bad problem with it.
You should do all the other easy thing 1st before you go tacking your intake off... it's kinda a shot in the dark thing.
yeah I did it but I tried things for years "I mean years before I tried knock sensors" I have an ls6 valley cover to and I did that at the same time... my AFR is a hair on the rich side so I’m not knocking because it's lean
I’m not knocking because I have oil in my intake.
I’m not knocking because I have an exhaust pipe banging on the floor pan
I’m not knocking because of low octane.
It’s not saying it’s not your sensors but I just think you should try to investigate other possibilities of the knock problem.
Any 98’s guys replace JUST their knock sensors and this fixed their knock problem? 100% no retarding of timing at part throttle and full throttle?
What is the max timing you see at WOT “before and after knock kicks in”
What rear? What rpm. Converter locked up? Part throttle knock? Gear/rpm, temp outside, coolant temp? What fuel table? What problem are you logging this what? If it’s autotap or efilive I can take a look at the logs
I could even post some of mine to compare…
These things are important in finding the source of the knock.
Is the car reducing timing at idle? Can you hear the detonation? I still have never heard my car detonate so I have always felt the problem was false knock or burst knock.
05-16-2005, 03:17 PM
#13
Thank you so much for your reply. I have hptuners so I am not sure if you are going to be able to open that or not. I will go a really break down when it happens. I am just afraid that I am going to remove to much spark and really screw something up. I guess there are a few things that I can look at.
I know that nothing is hitting the oil pan or under the car to help with knock. I am pretty sure that there is no oil in the intake, however I am not 100% positive. It could be from low octane but I am using 91 so I am going to rule that out. THis is on the auto car that I am tuning and it likes to do it after shifts. It will actually go as high as 8 or 9 at 1600 at .65 I think that is the grid #.
I am not sure how much timing is being pulled and I am pretty sure that it is not pulling timing at idle. Tonight I will go home and find all of the things that you were looking or asking about.
I know that nothing is hitting the oil pan or under the car to help with knock. I am pretty sure that there is no oil in the intake, however I am not 100% positive. It could be from low octane but I am using 91 so I am going to rule that out. THis is on the auto car that I am tuning and it likes to do it after shifts. It will actually go as high as 8 or 9 at 1600 at .65 I think that is the grid #.
I am not sure how much timing is being pulled and I am pretty sure that it is not pulling timing at idle. Tonight I will go home and find all of the things that you were looking or asking about.
05-17-2005, 11:50 AM
#14
Launching!
Join Date: May 2003
Location: Canadian West Coast
Posts: 290
Likes: 0
Received 0 Likes
on
0 Posts
Its definitely important to know at what rpm and tps it occurs, what gear, what MAF flow rate... Considering it is stock (including the tune?) it seems to SUGGEST that it is a faulty sensor, but not necessarily. Can you hear detonation?
05-17-2005, 01:25 PM
#15
Staging Lane
Join Date: May 2005
Posts: 54
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Camaro ChriSS
Its definitely important to know at what rpm and tps it occurs, what gear, what MAF flow rate... Considering it is stock (including the tune?) it seems to SUGGEST that it is a faulty sensor, but not necessarily. Can you hear detonation?
For example:
4400 RPM 5 deg KR at .64, 3 deg at .68, 2 deg at .72
Lower KR for the other RPM ranges , all in the .64 to .72 range
05-17-2005, 02:26 PM
#18
TECH Apprentice
Join Date: Jan 2002
Location: Princeton, IN
Posts: 364
Likes: 0
Received 0 Likes
on
0 Posts
Sevanseriesta,
Is a pinging sound... like marbles rolling around in the cylinders… sheet metal kinda sound?
A good way to test the knock sensors is take a large screw driver and tap the exhaust manifolds or around the front of the block close as you can get to the sensors as you can
Valve train noise can also cause the knock sensors to go off… they pick up on a 6 to 8khz rang so if you have any noise in that range or close to it your going to trip the sensors. They are fine tuned microphones that only respond to that range.
Dvanorder,
I have almost the same problem as you 4k rang and bam knock but not auditable, mine also detects knock around 1600 to 2100 rpms while the converter is locked up in 4th gear. What kinda timing do you pull at WOT? The max I see is 27deg that’s with or with out the pcm reducing timing. Does the car drop in to the low octane tables?
Bad sensors will most likely trip a code so I would have to say it’s not the sensors… but everyone’s problems could be different.
Try taping around on the block and exhaust to see if you can get the sensors to trip. You might have to use a ball peen hammer… this sound give a real close sound rang for the sensors to pick up on. “But don’t go and beat your block to death”
Taping around on my headers I can get the sensors to pull 4 or so deg at idle.
Is a pinging sound... like marbles rolling around in the cylinders… sheet metal kinda sound?
A good way to test the knock sensors is take a large screw driver and tap the exhaust manifolds or around the front of the block close as you can get to the sensors as you can
Valve train noise can also cause the knock sensors to go off… they pick up on a 6 to 8khz rang so if you have any noise in that range or close to it your going to trip the sensors. They are fine tuned microphones that only respond to that range.
Dvanorder,
I have almost the same problem as you 4k rang and bam knock but not auditable, mine also detects knock around 1600 to 2100 rpms while the converter is locked up in 4th gear. What kinda timing do you pull at WOT? The max I see is 27deg that’s with or with out the pcm reducing timing. Does the car drop in to the low octane tables?
Bad sensors will most likely trip a code so I would have to say it’s not the sensors… but everyone’s problems could be different.
Try taping around on the block and exhaust to see if you can get the sensors to trip. You might have to use a ball peen hammer… this sound give a real close sound rang for the sensors to pick up on. “But don’t go and beat your block to death”
Taping around on my headers I can get the sensors to pull 4 or so deg at idle.
05-17-2005, 04:09 PM
#19
Staging Lane
Join Date: May 2005
Posts: 54
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by dissonance
Sevanseriesta,
Is a pinging sound... like marbles rolling around in the cylinders… sheet metal kinda sound?
A good way to test the knock sensors is take a large screw driver and tap the exhaust manifolds or around the front of the block close as you can get to the sensors as you can
Valve train noise can also cause the knock sensors to go off… they pick up on a 6 to 8khz rang so if you have any noise in that range or close to it your going to trip the sensors. They are fine tuned microphones that only respond to that range.
Dvanorder,
I have almost the same problem as you 4k rang and bam knock but not auditable, mine also detects knock around 1600 to 2100 rpms while the converter is locked up in 4th gear. What kinda timing do you pull at WOT? The max I see is 27deg that’s with or with out the pcm reducing timing. Does the car drop in to the low octane tables?
Bad sensors will most likely trip a code so I would have to say it’s not the sensors… but everyone’s problems could be different.
Try taping around on the block and exhaust to see if you can get the sensors to trip. You might have to use a ball peen hammer… this sound give a real close sound rang for the sensors to pick up on. “But don’t go and beat your block to death”
Taping around on my headers I can get the sensors to pull 4 or so deg at idle.
Is a pinging sound... like marbles rolling around in the cylinders… sheet metal kinda sound?
A good way to test the knock sensors is take a large screw driver and tap the exhaust manifolds or around the front of the block close as you can get to the sensors as you can
Valve train noise can also cause the knock sensors to go off… they pick up on a 6 to 8khz rang so if you have any noise in that range or close to it your going to trip the sensors. They are fine tuned microphones that only respond to that range.
Dvanorder,
I have almost the same problem as you 4k rang and bam knock but not auditable, mine also detects knock around 1600 to 2100 rpms while the converter is locked up in 4th gear. What kinda timing do you pull at WOT? The max I see is 27deg that’s with or with out the pcm reducing timing. Does the car drop in to the low octane tables?
Bad sensors will most likely trip a code so I would have to say it’s not the sensors… but everyone’s problems could be different.
Try taping around on the block and exhaust to see if you can get the sensors to trip. You might have to use a ball peen hammer… this sound give a real close sound rang for the sensors to pick up on. “But don’t go and beat your block to death”
Taping around on my headers I can get the sensors to pull 4 or so deg at idle.