Cracked Exhaust Manifold Replacment?
 

2001 Monte Carlo SS 3.8 L

I believe its the left side for reference. I was told by a small independent muffler shop that I have a cracked a exhaust manifold and that my EGR valve line was also broken at the exhaust manifold. Consequently they don't do manifold work only exhaust pipes. I'm getting a 2nd opinion tomorrow at Midas. Although I think the muffler shop was spot on as I'm also getting "ticking" under acceleration and after reading around I see that is a tell tale sign of an exhaust manifold leak.

Is this a pretty involved repair? My buddy and I did a flexplate/flywheel so I can't believe it would be that difficult right? Are there any good write ups here I did a quick search but couldn't really find anything on how to tear this down and do the actual repair. Or maybe something on Youtube that would be recommended as following?

Thanks guys. :thumbsup:

You unbolt the rear exhaust manifold from the downpipe and from the rear head, unbolt the EGR and that's about it... Make sure to remove the spark plug wires and plugs too if you want to be safe.

Thanks man is that same procedure for the "right" and the "left"? There is a "left" and a "right" side correct?

What? There are bolts and studs that hold on the exhaust manifold... if you're talking about a "left and right" exhaust manifold that's for a RWD vehicle, ours are FWD hence back and front. But yes, same procedure minus the EGR for the front. Unbolt the crossover pipe, unbolt studs and bolts from manifold(s) and remove...

Might need to use some PB blaster on the crossover also. Just a heads up.

LOL ok thanks man I know just enough to be dangerous when working on this beast. So yeah OK front and back sounds better.

Thanks again brother. :thumbsup:

No problem man if you have more questions feel free to ask

Well Midas was unable to "find" a leak except at the flex pipe flange where it bolts to the exhaust manifold. They wanna smoke test it for $35 but I'm not sure I'm gonna go that route just yet.

Had my nephew look at it and he ran a scanner on it to pull codes and viewed the fuel trim data. The EGR valve line was loose where it meets up with the exhaust manifold and there was also another pipe that was loose right next to the EGR valve line and then of course its leaking at the flex pipe also. The flex pipe leak should be under warranty as that was just put on about 2-3 months ago with a new aftermarket Cat. I'll find out tomorrow afternoon.

Plus he said my PCV valve was not sealing (the rubber O-ring is hard and brittle) like it should and because the access cover to that was broken that holds the MAP sensor in by the last owner I'm just gonna buy an AC Delco kit and replace the rubber O-ring and broken access cover all in one. O'Reilly carries 'em for like $22 I think.

So at this point my nephew is strongly thinking that I do not have a cracked exhaust manifold but just a lot of other sh*t going on at the moment.

Thanks for taking the time to respond though. :thumbsup:

Permatex makes a high temp copper gasket maker. If you coat the flange surfaces in addition to the gasket it should take care of your exhaust leak. I used it at the track (cheaper then a stack of collector gaskets} to seal my collectors for the drive home. Never had a leak...

Thanks man I'll look into doing that. Yeah the garage that put on the new aftermarket Cat has changed hands so now the new owner says "What makes you think its leaking"? I said "Because I can feel it and Midas also told me it was leaking". Long story short they are not going to cover it and even told me "You'll feel some air in that area". I was dumb founded I told the dude "Yeah its supposed to be a sealed exhaust system you shouldn't be feeling air from the flex pipe flange".

But my nephew will fix it for free if I buy the gasket so I'll also look at that Permatex stuff tool. :thumbsup:

exhaust manifold crack and a leaking exhaust gasket have a lot of the same characteristics..... unless you've had cylinders misfiring or a lot of backfiring through the exhaust, I find it highly unlikely you cracked an exhaust manifold... those issues were mostly taken care of in designs in the 1980s as far as I know.

Thanks for the second opinion my nephew feels the same way. He thinks its a multitude of leaks like the flex pipe flange, and the cross pipe I think he called it which was near the EGR valve and of course the EGR valve line leaking. All that he thinks would have made the symptoms of a leaking manifold.

I am still p*ssed that the garage would tell me "You'll feel air in that area". I was like REALLY its a sealed exhaust system or its supposed to be why and how would I feel air in there? Then he tells me "Well I mean heat". LOL Yeah big difference there. Needless to say I won't be back to that garage now that it has changed hands. I don't deal with people that are crooked like that.

Plus my PCV valve is not sealing because of the rubber O-ring being worn out. So I bought the kit from Autozone and its supposed to be in I think they said tomorrow. So I'll get that changed out and see if that maybe helps my gas mileage.

My nephew said the fuel trim data showed that it was dumping a little excess fuel into the system and he's not sure why but that it might be from that PCV valve not sealing.

Technically speaking there's still LH and RH exhaust manifolds on FWD applications.. but I'm not going to start an argument.

LH would be front and RH would be rear. I have to deal with stuff like that at work all the time. They don't list parts by front or rear but most of the time the parts department knows what you're talking about.

I understand what you're saying, it's easier to call them front and back with a FWD car though IMO. Since the engine is mounted transversely and all that jazz. Thanks for bringing that point up though.

I noticed in looking at them they were labeling them "RH" and "LH". ;)

Thanks for all the advice guys.

Watsup so I'm trying to do something similar i want to swap a header set and want to change my rusted bolts. Anyone one where I can pick up a set of bolts or what there called? In having trouble finding them online or part stores and I'm trying to avoid going to the dealer that quoted me 62$