Replacing my knock sensors

[Duke Silver]

Hey guys,
So I have to put an order in for new knock sensors and was wondering if there's anything else while I have that intake manifold off of the engine that I should replace as well. I've seen videos and watch people talking about issues with the grounding I don't know if having that off would make it easier to get to that driver side area where the ground wire is and maybe I should take care of that. Somebody mentioned that I should change the o-rings on the fuel injectors. Just wondering what everybody thinks. Thanks.

 

[strutaeng]

Fuel injector o rings is a good idea, yes. I'm assuming you are a Gen III engine?

Valley cover gasket I'm assuming you are also replacing? The felpro kit also comes with the knock sensors seals.

Check the cam sensor (and oil pressure sender) back there to see if there's any leaks.

 

[OR VietVet]

Is the vehicle info a secret?

Knock sensor harness.

 

[Doubeleive]

Hey guys,
So I have to put an order in for new knock sensors and was wondering if there's anything else while I have that intake manifold off of the engine that I should replace as well. I've seen videos and watch people talking about issues with the grounding I don't know if having that off would make it easier to get to that driver side area where the ground wire is and maybe I should take care of that. Somebody mentioned that I should change the o-rings on the fuel injectors. Just wondering what everybody thinks. Thanks.

this is one of the best video's I have seen for doing the knock sensors,
my recommendation is to first use some engine degreaser and pressure wash the engine before you start, this makes life easier and gets rid of any material that may fall inside the engine while removing the intake. you can spray pretty much everywhere except directly in the alternator or electrical connectors.
once you have the intake off just clean stuff up a bit, check that the valley cover bolts are all tight, apply silicone around the new knock sensors and use a new knock sensor harness, there are tons of fake parts out there so either source your new sensors and harness from the dealer or a well known parts store.
reason being using a fake or aftermarket knock sensor pretty much means you will be doing this job twice!
I also recommend using the Fel-pro metallized intake gasket, cost a little extra but is a very good gasket and not subject to leaking down the road.
it is easier to replace the oil pressure sensor while the intake is off but if you are not having issue's with oil pressure then just leave it be.
follow the torque specs! do not over tighten the knock sensors and tighten the intake bolts in a cross pattern.

 

[Duke Silver]

Fuel injector o rings is a good idea, yes. I'm assuming you are a Gen III engine?

Valley cover gasket I'm assuming you are also replacing? The felpro kit also comes with the knock sensors seals.

Check the cam sensor (and oil pressure sender) back there to see if there's any leaks.

It's a 2005 so if I'm not mistaken I think that's a gen IV?

Sorry if it's a dumb question, It's the first time I'll ever be doing something like this I've been trying to learn on this vehicle, but is the valley cover gasket different from the intake manifold gasket? If so I did not know that and if you're recommending it I'll definitely add it to my list.

Sounds good about checking the cam sensor and oil pressure sender.

Thanks!

 

[Duke Silver]

Is the vehicle info a secret?

Knock sensor harness.

Haha, sorry

It's a 2005 suburban LT

 

[Duke Silver]

this is one of the best video's I have seen for doing the knock sensors,
my recommendation is to first use some engine degreaser and pressure wash the engine before you start, this makes life easier and gets rid of any material that may fall inside the engine while removing the intake. you can spray pretty much everywhere except directly in the alternator or electrical connectors.
once you have the intake off just clean stuff up a bit, check that the valley cover bolts are all tight, apply silicone around the new knock sensors and use a new knock sensor harness, there are tons of fake parts out there so either source your new sensors and harness from the dealer or a well known parts store.
reason being using a fake or aftermarket knock sensor pretty much means you will be doing this job twice!
I also recommend using the Fel-pro metallized intake gasket, cost a little extra but is a very good gasket and not subject to leaking down the road.
it is easier to replace the oil pressure sensor while the intake is off but if you are not having issue's with oil pressure then just leave it be.
follow the torque specs! do not over tighten the knock sensors and tighten the intake bolts in a cross pattern.

Thanks for the info I appreciate it. Would have never have thought to cleaned everything off so nothing falls down inside of there when I lift off that manifold. thanks for the video as well.
I'll check out that metalized gasket you recommend it. I did do my research beforehand and a lot of people were saying don't order anything off Amazon looks like it's safe to steer clear of eBay as well because of counterfeit parts. So right now the best pricing I can get for some ACDelco sensors is from summit racing so I'm going to order everything from there.

As far as the oil pressure goes in the car I have noticed ever since I've gotten it that as I'm driving it's typically around 40 but it will fluctuate between 40 and 20.

 

[Duke Silver]

Fuel injector o rings is a good idea, yes. I'm assuming you are a Gen III engine?

Valley cover gasket I'm assuming you are also replacing? The felpro kit also comes with the knock sensors seals.

Check the cam sensor (and oil pressure sender) back there to see if there's any leaks.

I also wanted to ask you any recommendations off of summit racing that you can recommend for the fuel injector o-rings? I know there's a couple different kits on there and I'm not entirely sure which ones I should go with. Thanks

 

[strutaeng]

I also wanted to ask you any recommendations off of summit racing that you can recommend for the fuel injector o-rings? I know there's a couple different kits on there and I'm not entirely sure which ones I should go with. Thanks

Go to RockAuto and follow your year and model. I ordered a fuel injector O-ring kit from RockAuto a few months ago for my 06 Suburban LQ4. It was a GM Genuine or AC Delco, can't recall the brand right now. Also, order the o ring with the fuel rail crossover pipe since you are basically going to take the entire fuel rail apart.

You should have the RPO code L59 5.3 engine (double check this on your glovebox) with flex fuel, which has injectors that are different than non-flex fuel.

Just be careful when working with the fuel rail because it will have a lot of gasoline when you remove it. Safety first!

 

[Doubeleive]

I wouldn't even bother with the injectors or the crossrail, that dam crossrail o-ring is a special size and no one carries it but the dealer and last time I had to replace one it was $40 for the 1 piece
unless there leaking I wouldn't bother
just my opinion

 

[Doubeleive]

It's a 2005 so if I'm not mistaken I think that's a gen IV?

Sorry if it's a dumb question, It's the first time I'll ever be doing something like this I've been trying to learn on this vehicle, but is the valley cover gasket different from the intake manifold gasket? If so I did not know that and if you're recommending it I'll definitely add it to my list.

Sounds good about checking the cam sensor and oil pressure sender.

Thanks!

valley cover is under the intake, you will see it when you have intake off rectangle metal cover with like 10 bolts.
if you pressure wash the engine beforehand you may find water around the knock sensors, which is not a big deal just soak it up with some paper towels first before you remove the sensors and applying the silicone around the rubber covers when you put the new ones in is to prevent the water from getting in there.

 

[Duke Silver]

I wouldn't even bother with the injectors or the crossrail, that dam crossrail o-ring is a special size and no one carries it but the dealer and last time I had to replace one it was $40 for the 1 piece
unless there leaking I wouldn't bother
just my opinion

Finally have the time to sit down and get the order together. So you're saying don't worry about the o-rings for the injectors, just take care of the knock sensors, harness, and replace the intake manifold gasket? Should I not worry about replacing the valley cover gasket as was mentioned by strutaeng? I've seen the video showing how to apply the RTV around the sensors so I'll be sure to do that. I attached a pic of what I have in the RockAuto cart and would like your advice on whether those parts look good to order.

 

[OR VietVet]

Make sure to use the 5% discount code.

 

[Duke Silver]

Make sure to use the 5% discount code.

What's the code?

 

[OR VietVet]

279092681252008661

Expires Oct. 18

Type it in to where it says, "how did you hear about us" and hit "enter" and you will see the parts price total change.

 

[Fless]

What's the code?

279092681252008661

Expires Oct. 18

Type it in to where it says, "how did you hear about us" and hit "enter" and you will see the parts price total change.

Why not lead him to the thread?

Rock Auto Discount Codes - Post 'em Here for Others to Use

Sept 6 27486975398013963 Thanks for keeping us with this Ron, you helped to save me $79 today.

www.tahoeyukonforum.com

 

[OR VietVet]

Why not lead him to the thread?

Rock Auto Discount Codes - Post 'em Here for Others to Use

Sept 6 27486975398013963 Thanks for keeping us with this Ron, you helped to save me $79 today.

www.tahoeyukonforum.com

Because I knew you would.

 

[Doubeleive]

Finally have the time to sit down and get the order together. So you're saying don't worry about the o-rings for the injectors, just take care of the knock sensors, harness, and replace the intake manifold gasket? Should I not worry about replacing the valley cover gasket as was mentioned by strutaeng? I've seen the video showing how to apply the RTV around the sensors so I'll be sure to do that. I attached a pic of what I have in the RockAuto cart and would like your advice on whether those parts look good to order.View attachment 440374

Unless the valley cover is leaking or you are getting lean codes or something weird then the valley cover and injectors are fine, no need to even mess with them. Just make sure the valley bolts are all tight otherwise while you have the intake off no need to open a can of worms

 

[Doubeleive]

If you really wanted to something else extra replace the valve cover gaskets if they are leaking, that's more common than anything else, those I would use the fel pro also and they come with new grommets

 

[Fless]

Because I knew you would.

You're SO dependent on others to cover for you.