Low voltage knock sensor code:24* of KR at 5800rpms. What is wrong?
#1
10 Second Club
Thread Starter
iTrader: (1)
Join Date: Nov 2001
Location: Boggy Creek
Posts: 1,528
Likes: 0
Received 0 Likes
on
0 Posts
Low voltage knock sensor code:24* of KR at 5800rpms. What is wrong?
Could the knock sensor have gone bad? I check the knock sensor wires to the PCM and they look good so i was thinking the sensor could be the only other culprit to throwing the code??
While auto taping the car i would see zero KR until 4000 rpms and at that point i would get 4* then at 5000 rpms i get 19* and at 5800 rpms i get 24* and stay at 24* until the car shifts into 3rd gear.
While auto taping the car i would see zero KR until 4000 rpms and at that point i would get 4* then at 5000 rpms i get 19* and at 5800 rpms i get 24* and stay at 24* until the car shifts into 3rd gear.
#2
TECH Senior Member
what's the exact P code?
If the PCM detects any issues w/the Knock sensors it'll automatically started using the low octane tables... and I believe in most situations it'll set a constant 4* of knock retard
If you clear the SES does it work properly? Or does it come back right away?
If it keeps coming back then we have a bad sensor or wiring issue... I'll try to find the Knock Sensor test procedure in a bit (there's a post in here that describes how to test the sensors to see if they're registering right)
If it's setting low voltage for both sensors then it's prolly wiring... if only 1 could be wiring or could be the infamous knock sensor water leak issue on pre LS6 intake cars... (assuming the front sensor is the one setting the code)
If the PCM detects any issues w/the Knock sensors it'll automatically started using the low octane tables... and I believe in most situations it'll set a constant 4* of knock retard
If you clear the SES does it work properly? Or does it come back right away?
If it keeps coming back then we have a bad sensor or wiring issue... I'll try to find the Knock Sensor test procedure in a bit (there's a post in here that describes how to test the sensors to see if they're registering right)
If it's setting low voltage for both sensors then it's prolly wiring... if only 1 could be wiring or could be the infamous knock sensor water leak issue on pre LS6 intake cars... (assuming the front sensor is the one setting the code)
#3
TECH Senior Member
#5
TECH Senior Member
Originally Posted by StreetStalkerZ
We were wondering if it was just setting a code from one sensor or both but we could not tell?
what was the code ? P0xxx (P1xxx works too... P1 codes are manufacturer specific ... but most of the GM P1 codes are known)
If it's setting low voltage for the KR sensor ... it must be a specific code... what was/is the code ...
#7
10 Second Club
Thread Starter
iTrader: (1)
Join Date: Nov 2001
Location: Boggy Creek
Posts: 1,528
Likes: 0
Received 0 Likes
on
0 Posts
Well i cleared the PCM this morning and drove the car around and the problem is gone with no SES light but i usually get a SES light after some driving anyway because of the converter. I figure if it's a wiring or knock sensor problem it should have came on after a few miles of driving. I will A tap again tomorrow night to see if im still getting some KR and will put more miles on it before i call it fixed.
Greg,im in the new house and settled in If i can get the car acting right it should be ready for some 11.0-10.90 passes in a few weeks,IF i can get some good weather. PM me and i'll let you know what is up.
Greg,im in the new house and settled in If i can get the car acting right it should be ready for some 11.0-10.90 passes in a few weeks,IF i can get some good weather. PM me and i'll let you know what is up.
Trending Topics
#8
On The Tree
iTrader: (1)
Join Date: Jun 2003
Location: Lexington KY
Posts: 137
Likes: 0
Received 0 Likes
on
0 Posts
I am having the same problem after a cam install. Pulls 4 degrees at WOT. Got a low voltage on back sensor...its been a while so I dont remember the exact code... I replaced the sensor and reset the computer...everything seemed good. Took the car for a spin and mashed it once...felt alot stronger...mashed it a second time and got a ses...Could a crimped wire...from the intake smashing it...cause a low voltage signal
#9
10 Second Club
Thread Starter
iTrader: (1)
Join Date: Nov 2001
Location: Boggy Creek
Posts: 1,528
Likes: 0
Received 0 Likes
on
0 Posts
Mine turned out to be a pinched wire on the PCM under the gray cover. I replaced the knock sensors and wireing harness under the intake and it worked for the first few WOT runs and then started all over again so i went back and replaced my old knock sensor wire under the gray cover on the PCM and the problem went away and has not been back since. I had this problem 2 years ago and spliced the wire and put a new wire in place of the pinched part but i guess the wire got old and was losing resistance and needed to be changed again.
Scott
Scott