Thread: P1133 Engine not running smooth?????

For a few weeks now i have noticed a small motor vibration but only from time to time. I know that intake manifold gaskets and upper plenum have never been done on the car and it has about 120 on the clock. Today out of nowhere the check engine light came on basically right at start up. When i got home and checked the code i came up with p1133 which is a fuel mixture issue? Possibly PCV problem however i know that the gaskets and plenum need to be done becasue i can see seepage around lower manifold gasket area and today it looks especially worse than last noticed. I am thinking maybe its time to just go do the manifold but i want other opinions of things to check before i dig in tomorrow. Thanks

Damn your good! So you dont think im due for the manifolds yet? I dont know where the fuel mixture thing came from. I just have a cheap generic code reader.

And just to verify B1 S1 would be located in the back of the motor (if standing in front) in the manifold someplace? Havent looked yet just wondering where to look. Thanks again!

I have been doing some research myself about the code. The diag write up from GM states that it is most likely caused by a contaminated sensor by either oil or coolant. Which leads me to believe that i do in fact need to do my manifold gaskets. Let me know if this sounds right to you.

Am i way out in left field or what? it got real quiet in here!

Well, if you can actually see leakage around your gaskets, and they've never been changed then it's time to change them. Might as well pick up a new O2 sensor while you're at it.

Has anybody heard anything about upgraded lower intake manifold gaskets? Suposedly they are made of aluminum instead of the common plastic with rubber gasket. Idk if it really makes a differense and if i should spend the extra money. Any ideas?

Are those the upgraded ones? I was on wbody store and they have the lower gaskets then it says +$5 for upgrade to aluminum gaskets. Suposedly its a new gm part. idk?

ok sweet! Thanks

Ok.... i got everything squared away. I bought the relocation coolant tank and the pcm mount and installed my intake. I ended up not even using the coolant tank and left the factory one and fabricated up a mount to the side of the tank. It looke pretty clean ill post pictures if i can. Except now i am not even happy with the way my intake sounds!!! I dont know if something is wrong or if this is just normal. I replaced my upper and lower intake gaskets and put the intake on it while i was under the hood. Every time i start it up now i get this god awful air noise that sounds like a really bad vacuum leak. I put my ear right next to the intake and thats what it is. I have put intakes like this on cars before and heard many many of them and have never heard anything like this. After a few minutes of warm up time it sounds like a normal intake should sound. Does anybody have any idea what is going on here? Or do i have to deal with this embarressment of a noise when i start my car around people.....

normal...with a cold air intake it sounds louder

Its not a normal sound. like i said i have installed intakes like this on other cars and i know its normal to hear the sucking sound but this is an unhealthy sound. The only thing i can describe the sound like is if you unplug your brake booster vacuum or any other vacuum line its loud and whistly......

ummmm....do you have a scanner that you can check you ltst and stft's to see if there are any vac leaks...but then again you said it goes away shortly after startup right?...wich would make it not a vac leak...ummmm idk anyone else?

you said it was commming through the intake....i cant think of anything that would cause any abnormal noises that is not OUTSIDE of the motor...i mean i cant imagine you could of done anything to make it sound like that...i just cant see it happining....


i know you dont think it is normal but the sound mine makes on a cold start up is very loud also...too bad there isint anyway you could get a goodenough sound clip so that we could tell....