I’ve had a code pop up off and on and it refers me to intake gaskets. I’ve put new ones on well before getting this code. My heads had been shaved but not sure how much. I see they sell different thickness intake gaskets for the LS. Should I try a set of these and can I go to thick?

 

If you shaved the heads, theoretically you would need THINNER ones. However, the LS doesn't use gaskets on the intake, it uses O-RINGS. You would know this if you have EVER seen one disassembled. Someone's blowing smoke on this one.

 

Let me rephrase then O-RING and I have taken the intake off. So why do they sell thicker ones. Tap the link below smarta$$

https://ls1tech.com/forums/attachmen...1&d=1512168062

 

I was only going by what you said above. So the rudeness can stop RIGHT NOW!
Yes they sell thicker ones, but for another application. If you have the right ones for your app, one might be leaking. Did you remove the intake before this issue?
And I tapped the link. It comes back invalid. Try again.

 

What is the code that pops up ?
Is this on a stock original ls1?
Ls1 or Ls6 intake ?
Egr or is that deleted ?

 

I tapped the link and works fine for me. It comes up fel-pro intake “gaskets” listed for LS engines. What I said is not incorrect. I guess fel-pro is wrong lol. Anyway it shows different thickness available.

 

It’s just a LS1 with cam, headers and LS6 intake. This is in my 64 nova so no emissions stuff. My map sensor was a source of vacuum leak but fixed that with a new seal. Cleaned LS3 style maf sensor. 02 sensors are good. Replaced intake o-rings but still pops up time to time,code. Tuner noticed the 02 sensors pouring fuel in at idle and part throttle. That’s when we found map leak.

 

Alright, how do they say to use the different thicknesses? There are different manifolds available aftermarket for the LS1 and other LS engines, and some of these O-rings might be for them. There is no reason to vary thicknesses for a single application. Are you experiencing vacuum leaks right now? And I did NOT say Fel-pro was wrong, nor even imply it.
The message I get on the link comes from LS1Tech, so it's not your fault either.
Which code # pops up? That will help others here who might help you.

 

I would make sure the intake is seated all the way. Even if the heads were milled .030" - .040" the intake should still seal.

Is the bottom of the Ls6 intake ground down?

Is the bottom of the intake slightly hitting the knock sensors or knock sensor wires.....

 

Ya, a code number would help lots

 

PO172 If I remember right.

 

I’m getting ready to swap over to the LS6 pcv system to eliminate the extra lines and possible leaks. Suppose to be a better set up they say anyway. Just got it delivered today.

 

If that is correct, the causes listed are:
-Faulty heated front O2 sensor
-Ignition misfiring
-Faulty fuel injectors
-Exhaust gas leaks
-Incorrect fuel pressure
-Faulty MAF sensor
The code is activated by too rich a mixture
NONE of this is related to intake sealing, by the way

 

Just got home and hooked my scanning tool up and it shows PO174( my bad)system too lean.

https://ls1tech.com/forums/attachmen...1&d=1512181668

 

https://ls1tech.com/forums/attachmen...1&d=1512182063

These are what I’m inquiring about.

 

The intake isn’t ground down or anything. When I swapped intakes and put the new o-rings on I can’t say for sure it wasnt hitting anything. Pretty much just set it in place and torqued it down. Is this a common issue with intakes hitting that stuff?

 

Another place to check is on the passenger side there is a tube that is wrapped in foam that is part of the pcv system. It runs right below the fuel rail.
There is a section in there were it connects to another section that's a slip fit that sometimes disconnects when rejoicing the intake causing a lean code.

 

Yes, the bottom fins on the bottom of the Ls6 intake absolutely have to be ground down otherwise the steam pipes and some times the knock sensors will prevent it from seating all the way.

 

Like this.

 

No problem man!
The causes are:
-Dirty or faulty MAF
-Vacuum leak (manifold O-ring??)
-Fuel system problem (rail, injectors, pump, regulator)

So now that we have the correct code, you know what could be it. And the manifold seal IS one possibility! Try a test where you spray WD40 around the ports to see if it does anything. Any leak will become evident.