I had my SES light on, i checked it and it gave the code for the knock sensor. What does this do and where does it go anybody please.

 

Knock sensors are located under the intake in the intake valley cover. If you pull the intake off you will see two plugs in the valley cover that pull out and the knock sensors are located below in the block. Are you getting a code for a bad sensor or a code for knock retard?

 

Heh.. since you've got a 98 if it's got a lot of miles on it and hasn't had the GM TSB done on it you're knocks could just be a tad corroded and thus one has gone faulty on yah. There's some shitty foam under the intake that GM issued a TSB to remove since it held moisture and eventually corroded the tops of the knocks on folks.

If it's knock retard (which you probably have since you've got a 98) then you can fix that through tuning and stuff. Since you threw an SES it'll be a faulty sensor code or something related to this. Also, if you're throwing a knock sensor code you're knock learn factor will be dead 0.0 and you'll be in your low octane table. That will blow since you will be getting low 20's for timing at WOT when you should be getting 28 degrees.

Best of luck bud. Hope this helps.

 

Im gonna have to double check to make sure what it is. I just got it tuned so the knock retard should of cleared right? If it is the knock sensor im gonna change both cause it is two arent they, and probably while at it do an LS6 Manifold swap, is there anything special ill need for the swap?? i will stay with the EGR system probably.

 

Sorry to intrude on this thread, but I've also got a 98 and my damn knock sensors were pulling my timing below 20 degrees some times at WOT. How the hell do you figure out if it's actually "knocking" or just the sensor?

 

Whatever it is, you should swap out those '98 sensors anyway.

 

"How the hell do you figure out if it's actually "knocking" or just the sensor?"

Run 98+ octane through it and see if the knock persists. If not, it's fake knock and can be tuned down (via HPTuners, you modify the sensitivity ) or upgrade to newer knock sensors (01+).

 

Sounds good. I assume that there is nothing special about switching out the knock sensors with the newer ones, correct? I'll plan on doing that when I buy and install a new intake. Anyone know how much they are? I'll start looking. Thanks!!

 

Put RTV/silicone around the new ones when you install them to form a good seal. VERY easy to replace. Cost - not sure.

 

I just got them for 35 a piece.

 

You guys will have to get a new wire for the new sensors too. Also, remove that foam square under the intake, it wicks and holds water, causing the sensors to corrode.

 

Yep, that foam removal is important. My knocks are still **** in my 98 but I just turned them down for now. An intake is coming for the car in the fall months, I'll change them then.

The HP Tuners table you modify is under spark control > knock retard > knock sensor global gain vs. rpm vs. MAP. Set the cells that are 0 in the upper regions of the table to 2.0 to start. If that doesn't quite cure it try 3.0, and then finally 4.0 (basically shutting them off.... hope you run good gas)

Also.. besides KR being a bitch I grew up on old school rides. Running a distributor and carb on anthing non computer controlled and you'd adjust for knock by sound. The motors always ran for a long time. You'd also check spark plug burn and such to ensure it was running right and not too lean or rich. Our LS1's are great technological marvels but the old adage still applies. If you run GOOD gas in the car and run a STOCK timing table and don't have any crazy mods (huge cam, wicked heads.. both) chances are you're not going to knock.

Also, you should still be able to hear it if the car is knocking. Pennies in a pop can sound.

 

Is there a TSB on this? My 02 has the foam inserts.

 

Yes, there is a TSB but I don't have it handy. You might want to try a search here, but basically, you remove the foam square under the intake, and then make an RTV red silicone dam around the knock sensors with an opening toward the firewall to let water drain out. That's basically all the TSB contains.

 

So, there aren't any drawbacks to switching to the newer style knock sensors, right? Are the newer ones just less sensitive, more accurate or what? I assume we can just order the new wires we need when ordering the sensors, correct? Thanks again for all the help and advice. I've been wondering about this stuff for a while now...

 

The drawbacks are with the '98 sensors, they don't work properly. It's just one wire you need that attaches to both sensors and the connector behind the intake.

 

Yup just like Predator says. Your 02 probably has decent knocks so unless they corode or you have your intake off for some other reason I wouldn't worry about it.

I only drive my car in the summer and rarely if ever in the rain so it's not that big of a deal for me. I'll be doing the RTV and 99+ knock sensor upgrade when I pull my intake in the fall though.

 

Exactly, just be careful washing your engine too, that's how I ruined my '00 sensors. I sprayed water behind the intake. Now I just use a light mist of water staying away from the back of the intake, and I do a lot more wiping to clean the engine, but it's worth the extra effort.

 

hey guys i have a 98 ss now i wanna upgrade the sensors,so wat are the best years?were do u buy them at?and wat are the wire part numbers or do u cut and splice because i wouldnt likt that give us all the info for them 98 boys

 

I'll build a RTV damm. It so happens I have the car apart, so now's the time.

I can see how there could be a problem. It was nasty under there even though the rest ofthe engine bay was spotless.

Thanks for the tip!