Exhaust in the engine bay?!?!

[gsxcellent]

I have just recently performed a throttle body and intake cleaning job using Sea Foam and this is where i realized that the smoke that should all blow out my exhaust (cleaning out the carbon) would leak out of my engnine bay from under the right front side of the valve cover...(not the valve cover gasket but further down on the head). It cant be normal for exhaust fumes to escape from the engine could it?

PS. This would only happen when reving the engine AKA i could have been under boost.
Thanks in advance!

 

[Black94DSM]

Leaking Exhaust manifold gasket ? Or are you talking about further down where the head and block mate.

 

[SBstar]

Sounds like you're talking about the headgasket, probably time for a replacement. Unless I"m confused and it's leaking out around the manifold, which would be the manifold gasket.

 

[gsxcellent]

See i was thinking blown head gasket as well but ive run into that problem before and i ran a compression test and showed up with around 178 pounds in each cylinder(perfect)!?! The DP gasket is fairly brand new because of my turbo back exhaust, possibly bad?

 

[Slapnut]

There are 2 types of head gasket blow outs, antifreeze / oil in cylinder or antifreeze into oil. You might want to check your exhaust manifold itself for cracks, my stock manifolds where both cracked and leaking.

 

[andymoraitis]

If you have heatshields on the car, pull them off when doing your test and you'll see exactly where the smoke is coming from. From what you're describing it's not the headgasket, but the manifold gasket. Look for any black discharge from underneath and towards the top of the manifold where it joins to the head as this will be a telltale sign of an exhaust leak.

I'd go after this pretty quickly since a pre-O2 exhaust leak will kill performance.

Let us know what you find,

Andy

 

[Winky]

Quick note on additives like sea foam... yes they do break up build ups but this may not be completly beneficiary. The stuff you are trying to get off (most likely oil build up or something) has probably formed around the seals of your engine, so by removing them may cause leaks....

Please do not post myths you've heard from grandma.

 

[gsxcellent]

Thanks Slapnut, i guess if ## right it will give me an excuse to finish my exhaust system with some headers . Will check this out tomorrow as its 1:30am now.

 

[gsxcellent]

andymoraitis, you may have just solved my other post about a performance problem i have been having for some time now....for more check my post subjected "Severe stuttering around 3k or 12psi!!!!"

Thanks for the help so far!

 

[andymoraitis]

No problem, that's what we're here for. Pre-O2 exhaust leaks can cause driveability issues and considering that around 3K is where most turbos start to really sing, that could explain a great deal. Just make sure to pull those heat shields when you seafoam it so that you can pinpoint the exact location. I had one post O2 at the downpipe and all that did was create a minor exhaust leak. You may even find that it's leaking at the 02 gasket which will have similar effects.

One of the other posters above mentioned possible manifold cracks and that's a great point. The gasket may be fine, but if the manifold's cracked it'll have the same effect.

Stay in touch and let us know what you find,

Andy

 

[gsxcellent]

Thanks again, ill get back with the results ASAP!

 

[gsxcellent]

Ok so i removed the heat shield and revVed the engine...there is definately exhaust coming from where the manifold meets the head on the right side. Good and bad news i guess. How difficult are those bolts to get off and would a 2g non turbo gasket fit this? (already have one from the old gs)

 

[SBstar]

The gasket off of a 2g non turbo will not work on your turbo 4G63. The bolts should actually be studs and the nuts will turn off. There is a good chance some of the studs will break off though (unfortunate but true) Just try your best to be careful when removing them. Don't go with a cheap gasket either, I would suggest a 4 layer mitsu gasket if you plan on running alot of boost.

 

[D_Eclipse9916]

Quick note on additives like sea foam... yes they do break up build ups but this may not be completly beneficiary. The stuff you are trying to get off (most likely oil build up or something) has probably formed around the seals of your engine, so by removing them may cause leaks....

Please do not post myths you've heard from grandma.

Sorry defiant but that isnt a myth. Its true, I I developed small leaks around my spark plug o-rings after using seafoam on my gs. It had 27k miles and ran like a top, did it, my spark plug o-rings started to leak right after that.

This is the reason why I Wont use seafoam until right before im replacing all the valve cover gaskets, just in case it wants to leak.