PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

Pulling a Knock Sensor Code

Thread Tools
 
Search this Thread
 
Old Oct 14, 2003 | 08:27 AM
  #1  
Bowwdown's Avatar
Thread Starter
Teching In
 
Joined: Apr 2003
Posts: 8
Likes: 0
From: Scarborough
Default Pulling a Knock Sensor Code

Jusat wondsering if anyone on here has had this same problem ..... I scanned the car and came up with a po327 code which is Knock Sensor /Sensor 1

The car is also picking up a miss on Cylinder 6 . I canerase the code and it usually comes back on within 10 minutes of driving .

Any recommendations ?

The only mods I have are the following .... True Dual Exhuast ( 2.5" with X-pipe and dual Magnaflows ) ,Carsound Convertors and K&N fipk ....

Thank you in Advance , I also only run 93 octane and up gas and have seemed to have had a detonation problem on the highway when it gets stomped on .

Thanks ,
Rick
Reply
Old Oct 14, 2003 | 05:34 PM
  #2  
horist's Avatar
TECH Senior Member
 
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
Default Re: Pulling a Knock Sensor Code

search in the pcm/electrical section... lots of posts about that and what it could be...

I had a PO327 code after I did my heads/cam... replaced knock sensors... didn't go away, replaced PCM (i have a spare) didn't go away... finally when i pulled the intake again and found a wire was grounding out between lifter valley cover and block (I changed to LS6 lifter valley cover)...

Now this probably isn't your problem since you haven't taken the intake off... but a few things to check...

1. Search PCM section, there's a procedure in there for troubleshooting this code (shows you what wires to test with a digi ohm meter)...

2. Check the connections are the PCM to see if any of them are corroded

3. You didn't post what year car you have... but there was a problem is some cars (not sure of years) where water would seep under the intake manifold between the intake and the lifter valley cover... this water would then settle in the opening where the knock sensor plugs in and cause the knock sensor to short out/go bad....

If this is the case you'll have to pull the intake, and replace the front knock sensor (if you don't want to replace you can try swapping the knock sensors, if problem follows sensor then that sensor is bad, if problem doesn't follow sensor then you have a wiring problem somewhere)


if you're experiencing detonation at WOT and running 93 and setting a code for misfires on cylinder 6 then check the plug in cylinder 6 (from front of car, 3rd cylinder back on passenger side).. the injector could also be partially clogged so you're not delivering enough fuel... also have you descreend your MAF? if so this can cause a car to run leaner and could contribute to your detonation issue... also if you have atap check what your O2s are reading during WOT (should be .920-.930 or so) and verify your LTRIMS (Long Term Fuel Trims) are close to zero or slightly negative (if theyre way outta spec then this could also be causing your misfire condition)

If it were me I'd check the spark plugs and wires first (make sure the wire's ok and not arching or didn't get burnt by headers if you have any). If everything looks good there, pull intake manifold and install new knock sensor (or swap them, but you'll have to pull the intake again to fix the problem if it really is the knock sensor), also do the fix (in PCM section under p0327 topics) where you use silicone to prevent water from getting to the knock sensors...

while intake is off, follow the knock wires to make sure nothing's burnt/chewed through/pinched (Knock sensor wires go in back of car, and connect to a connector in back of drivers side head).

If problem is still there then (misfire on cylinder 6) try some injector cleaner... but the po327 code should be gone... if you still get misfires on 6 could be the injector (you could swap injectors while the intake was off, to see if the problem follows the injector)
Reply
Old Oct 15, 2003 | 10:49 AM
  #3  
Bowwdown's Avatar
Thread Starter
Teching In
 
Joined: Apr 2003
Posts: 8
Likes: 0
From: Scarborough
Default Re: Pulling a Knock Sensor Code

Sorry , I have a 1999 Z28 with 69,000 kms . I also had NGK TR6's in it . I was going to run Nitrous , So I pulled the plugs and put Delco plugs back in . I have never had the intake off . I tried to find the troubleshooting in the PCM forum .. but I had no luck .

Thanks for all your help
Rick
Reply
Old Oct 15, 2003 | 02:25 PM
  #4  
horist's Avatar
TECH Senior Member
 
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
Default Re: Pulling a Knock Sensor Code

https://ls1tech.com/threads/showflat...rue#Post328806

since you're only getting one code (and not getting the code for both front and rear knock sensors) I'd guess your front knock sensor is prolly bad...

part number is 10456603
Reply
Old Oct 15, 2003 | 07:23 PM
  #5  
Bowwdown's Avatar
Thread Starter
Teching In
 
Joined: Apr 2003
Posts: 8
Likes: 0
From: Scarborough
Default Re: Pulling a Knock Sensor Code

I ran the scanner tonight and here are some of the things I pulled

Ign Tim Adv Cy 20.5-2.5 (idle) 33.0-47 ( WOT )
a.i.r pump off
a.i.r sol off
MAF S1 GLS 6.82

Knock Retard 0.32 (idle) 101.48 (wot)

Misfire Index 120 (idle) 230 (wot )

IDLE o2 volts B2 S1 0.0824 to 0.800
B2 S2 0.090 to 0.095

Fuel Tank Pres Volt 1.48
Fuel Level LF Tn 1.96

Misfire current #7 121
Misfire Current #8 0
His #7 0
His #8 0

Total Misfire 2

ECT Deg F 186
C 86

Map Volts -0.55

IAT Deg C 35
F 95


Does any of this **** mean anything

When I was going WOT the Scanner was showing
Knock Signal 0

Thanks Again

Rick
Reply
Old Oct 15, 2003 | 08:29 PM
  #6  
Bowwdown's Avatar
Thread Starter
Teching In
 
Joined: Apr 2003
Posts: 8
Likes: 0
From: Scarborough
Default Re: Pulling a Knock Sensor Code

My wife and I just went out in the car with the Scanner attached ....

We were watching Ignition Timing Advance Cy and While cruising we were bouncing between 23 and 40

But when I punched it it would drop to 18 and stay there .

So is it picking up detonation ??

Rick
Reply
Old Oct 16, 2003 | 07:52 PM
  #7  
Bowwdown's Avatar
Thread Starter
Teching In
 
Joined: Apr 2003
Posts: 8
Likes: 0
From: Scarborough
Default Re: Pulling a Knock Sensor Code

Anyone have any thought into the numbers I posted ... Does it seem like is running normal??

Rick
Reply
Old Oct 17, 2003 | 12:28 PM
  #8  
horist's Avatar
TECH Senior Member
 
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
Default Re: Pulling a Knock Sensor Code

bouncing 23-40 is normal, you're not under much load cruising so you can get higher timing..

the 18* of timing you're seeing at WOT seems really low... probably the same issue I had...

From my understanding when a P0327 code is set (problem w/knock sensor) the PCM drops into the low octane tables (considerably less timing)

The value:
Knock Retard 0.32 (idle) 101.48 (wot)

is an autotap fluke... 101 KR isn't possible...

at WOT (TPS > 96% or so) I bet you're seeing constant 4* of KR? *edit, saw you said you're getting 0*... one thing to try... reset the PCM (easiest way, discon battery for an hour and then recon), then go out at WOT, see if your timing is alot higher at WOT, if it is then you're being dumped to the low octane ignition tables, most likely because of a bad knock sensor)

When the PCM detects a problem w/the knock sensors it'll drop you to low octane timing tables, and sometimes (maybe always?) show 4* or KR at WOT (instantaneous)

Sounds like you most likely have a bad knock sensor...
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo




All times are GMT -5. The time now is 09:14 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE