P0327 Knock Sensor - Performance??

**desliger** · 01-26-2007, 06:13 PM

Hey Guys,

I'm pulling a P0327 code, although I'm sure my car is not knocking/pinging at all. I know I need to check my plugs and wires to be on the safe side though, and I only use premium gas.

2002 SS
73K miles

I know with my mileage, the actual sensor could be going out, but once in a while my SES light will turn off, and then come back on when I start driving (making me think there is an actual knock/ping). I usually drive my car pretty normal, and it seems when I don't get on it for awhile the SES light will go off. But once I do get on it, it will come back on...

With this code, is my car pulling timing by 3 - 4 degrees (what I've read)? Also, when my SES light is on because of P0327 (it is always on now), will this affect my performance? If so, how much??

Thanks everyone!! (BTW, I got to keep my job... lol)

**desliger** · 01-30-2007, 08:54 AM

Hey Guys,

I just wanted to let everyone know that I purchased, and will be installing the following on the weekend (if everything arrives in time):

2 Knock Sensors
Intake gasket
NGK TR55IX spark plugs
MSD 8.5mm wires
K&N Air Filter

I think this should resolve any issues I'm having.. I was just curious if the P0327 would hurt my performance, and if so, how much.. If anyone knows... lol

Thanks Guys!!

**desliger** · 02-04-2007, 03:11 PM

Just for the record book...

I changed my plugs/wires and fuel filter... WoW! What a difference! First time I got on it, the SES light turned off, and it hasn't turned on since...

I guess I won't have to put the knock sensors in after all!!

As far as performance goes, there is a BIG difference, I'm not sure how much, but WOW!! The car runs soo smooth now, you can really tell on the top end!!

**desliger** · 02-10-2007, 02:08 PM

The SES light came on the other day, I'm removing the intake today... so if anyone has any helpful hints let me know...lol Thanks!

**2001NBMZ28** · 02-10-2007, 02:39 PM

For the knock sensor again? Man, thought you had it. Be careful you don't break the oil pressure sensor behind the intake on the drivers side - happens all the time, and don't pinch the harness for the sensors when reinstalling. You're doing the right thing by replacing both sensors while the intake is off.

**89LX** · 02-10-2007, 02:47 PM

Even though not a LS6 FAST has a very good write-up that will get it done for you.
http://www.fuelairspark.com/Base/Ins...nFiles/147.pdf

Make sure you lift the rear of the manifold before you start sliding it forward. If you don't the oil sensor can and probably will be damaged. It sits in a recess (hemmed in by the manifold) and if you try to pull straight you will break it off. I got a blanket and laid accross the engine. With all but the back four removed use them (to help hold up the rear) and slid forward. Same going back. Not that bad but a bit time consuming unless you have done before (I was a rookie) in my opinion.

**2001NBMZ28** · 02-10-2007, 03:13 PM

There's also a good writeup with pics on the LS1/LS6 swap at www.ls1howto.com that gives some pointers.

**desliger** · 02-10-2007, 03:58 PM

Thanks for the responses! I have got all of the bolts out of the intake, I'm just waiting on some help to come so I can remove the intake... or I might have to wait till tomorrow morning... Either way, thanks for the help!!!

**LS1Chris** · 02-11-2007, 06:20 AM

I had the same problem a few months ago...I got the code read at AutoZone for free, then had to get a new sensor for the front one...installed that a week later and it has been good for 2 months...then the code came back but for the rear one!

I've resetted it a few times by turning the key to RUN and pulling the PCM BAT and PCM IGN fuse to clear the code...but in day to few, it comes back. Pretty sure it's the rear sensor because it has a light rust around it and the front one is a new one. I should have replaced them at the same time but didn't have time to get another one.

Right now I've been driving like this for 3 months and will install the rear sensor when the weather warms up.

I've been told washing the engine bay causes the sensor to work intermittely and damages them due to corroision.

**desliger** · 02-11-2007, 09:34 AM

Yeah, I'm pretty sure the sensor came on after I washed the engine!

I heard someone say something about creating a seal with RTV? I'll look that up...

After getting the intake off this morning, I noticed the engine had a lot of oil on the intake runners. I looked inside by the valves, and it is really clean on the inside though... Maybe my PCV valve is bad? It doesn't seem bad, I can shake it and hear the ball moving free... My throttle body was a little oily, and where the PCV valve sits, the outside of the engine was a little oily too. I did notice a slight crack in the PCV tube though..

When changing the knock sensors out, did anyone notice the intake ports being oily like mine? I'm a little worried about that, but I'm going to clean the ports/intake/throttle body out before I put everything back together..

I'm going to pull the intake valley cover off and see if I can put an LS6 one on, and redo the PCV system like on LS1howto.com.. That system seems like it would work better..

Again, thanks for the help!

**2manycis** · 02-11-2007, 11:18 AM

One problem I've seen with a lot of chevys(maybe not yours), is that the front main seal starts leaking oil on the cps and causes it to mess up, hence the light coming on and off...

This is mainly a problem with v6 s-10s, but could be worth looking into.

**98Camarod** · 02-15-2007, 02:55 PM

I deleted my pcv system and do not have oil in my intake anymore. My line on my driver side was barely held together.

**YoMommasTA** · 02-15-2007, 05:17 PM

Originally Posted by desliger

Yeah, I'm pretty sure the sensor came on after I washed the engine!

I heard someone say something about creating a seal with RTV? I'll look that up...

After getting the intake off this morning, I noticed the engine had a lot of oil on the intake runners. I looked inside by the valves, and it is really clean on the inside though... Maybe my PCV valve is bad? It doesn't seem bad, I can shake it and hear the ball moving free... My throttle body was a little oily, and where the PCV valve sits, the outside of the engine was a little oily too. I did notice a slight crack in the PCV tube though..

When changing the knock sensors out, did anyone notice the intake ports being oily like mine? I'm a little worried about that, but I'm going to clean the ports/intake/throttle body out before I put everything back together..

I'm going to pull the intake valley cover off and see if I can put an LS6 one on, and redo the PCV system like on LS1howto.com.. That system seems like it would work better..

Again, thanks for the help!

yep completely normal

**desliger** · 02-15-2007, 07:48 PM

It's good to know that's normal!!

I went ahead and bought the LS6 valley cover, my brother did the cut out on the block (he's an expert with a dremel). Now I'm just waiting for the PCV system, and the new knock sensor wiring harness to come in at the local dealership....

**Steve Crowe** · 02-18-2007, 08:07 PM

Just an aside on knock sensors - -

Sometimes when you've changed your exhaust or have a radical cam they'll pick up on things the PCM doesn't learn to tune out, in that case there's an old trick you can use IF YOU'RE SURE the KR isn't real.

Take off the sensors and wrap them with a few turns of common black electrical tape which will slighlty desensitive them. In extreme cases you can use snips of Dynamat but if it's that bad you best go for quieting the source rather than applying a Band-Aid. :-)

**Z-Boy** · 09-22-2009, 06:54 PM

Any one ever replace knock sensors on a 98 Z-28 Any advic e would be helpful.

**EVIL-LS1** · 09-28-2009, 08:03 PM

My SES light on and I took it in and they said the code was a knock sensor. They cleard the code. I have been running 93 octane and I have raced it at the track 3 times and its been a good month and the light hasnt came back on. Do you think it might of been low octane gas cousing the knock sensors to throw the SES light on..

**0rion** · 09-28-2009, 10:49 PM

Originally Posted by Z-Boy

Any one ever replace knock sensors on a 98 Z-28 Any advic e would be helpful.

have you ordered them yet? If not order the sensors and harness for the 99+ cars. The 98's sensors were really sensitive. Other than that it's a pretty straight forward install. Look at ls1howto.com at the intake swap and it'll give you step by step on pulling the intake. Watch the brake booster hose because it will break your oil pressure sender off and you'll be replacing that like myself and thousands of others have done.

**0rion** · 09-28-2009, 10:50 PM

Originally Posted by 1Bad97Ram

My SES light on and I took it in and they said the code was a knock sensor. They cleard the code. I have been running 93 octane and I have raced it at the track 3 times and its been a good month and the light hasnt came back on. Do you think it might of been low octane gas cousing the knock sensors to throw the SES light on..

it really depends on what code it was. Do you wash your engine bay with a water hose? Water will kill knock sensors pretty quickly.

**Ramair1** · 09-29-2009, 04:00 AM

Originally Posted by 0rion

it really depends on what code it was. Do you wash your engine bay with a water hose? Water will kill knock sensors pretty quickly.

Also make sure the knock sensors do not have any corrosion on them when you do check them. While checking them, make sure build up a bead of silcone around each sensor opening to keep water out in the future. Check the wiring harness as well making sure there is no cracked wires/insulation and all connectors look in good condition.