2006 z71 brokem manifold bolt

Hi all,
Kept getting the catalytic converter inefficiency code, it was intermittent and could go off at any time.(bank 2). Dealer said nothing wrong, converter runs fine, temps and voltages spot on when at temp. Code keeps coming back, Tried the friendly neighborhood mechanic, said the same thing.(at least it was a lot cheaper to be told the same thing). But he said if it keeps up might have to replace converter.All o2 sensors are new. I asked both places if they checked for an exhaust leak and got a blank stare.I tried to do a smoke test with a fog machine and water soluable fog but i don't think it was staying in fog form and condensing out before it was of any use to me.  At least in doing this i finally noticed the nasty broken bolts on my exhaust manifolds. I'm hoping It could posiibly explain the code that has no explanation, and why it is intermittent.
Any one here done this repair themselves? I would love to tackle this one, but i don't want to get into anything that needs any specialised equipment. I can do a drill out and use an easy out if needed.
Should i go ahead and replace the whole shebang or just swap out the bolts and gaskets?
I'm also hoping this would stop the code and keep me from actually losing a cat.
any advise greatly appreciated.

thanks

You can search the internet and find lots of GM truck owners who've found themselves in the same situation.  You may want to Google, Bing, or use whatever your favorite search engine is to find a lot of info on what others have done and how much time and effort it took them to get the broken bolts out.

When i put put my lt headers on it had two studs broke before i started. Mine had just enough out to use pb blast and vise grips

enoniam said:

You can search the internet and find lots of GM truck owners who've found themselves in the same situation.  You may want to Google, Bing, or use whatever your favorite search engine is to find a lot of info on what others have done and how much time and effort it took them to get the broken bolts out.

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Did search, that's why I'm here at the avalanche forum and not the dodge neon forum. I'm in the section called problems, engine. it's in the section called problems, questions and answers.I also know what bolts i have to order and have the gaskets needed to do it. Saw a lot of garage people take them out with welding bolts on to them but not many regular home mechanics.

snafup said:

Did search, that's why I'm here at the avalanche forum and not the dodge neon forum. I'm in the section called problems, engine. it's in the section called problems, questions and answers.I also know what bolts i have to order and have the gaskets needed to do it. Saw a lot of garage people take them out with welding bolts on to them but not many regular home mechanics.

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Sorry.  I'll know next time if I can't answer your question not to make suggestions on how to find the answer. 

ouch!

snafup said:

Did search, that's why I'm here at the avalanche forum and not the dodge neon forum. I'm in the section called problems, engine. it's in the section called problems, questions and answers.I also know what bolts i have to order and have the gaskets needed to do it. Saw a lot of garage people take them out with welding bolts on to them but not many regular home mechanics.

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NO Reason for this type of response when a member was trying to help you with your issue...

Please Keep the peace.

enoniam said:

Sorry.  I'll know next time if I can't answer your question not to make suggestions on how to find the answer. 

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He deserves that. Instead of just wanting someone to tell you everything, you learn more when you take the time to read all threads related to his problem. enoniam may have skipped something that the OP could see if he did the search himself. 

snafup said:

Any one here done this repair themselves? I would love to tackle this one, but i don't want to get into anything that needs any specialised equipment. I can do a drill out and use an easy out if needed.
Should i go ahead and replace the whole shebang or just swap out the bolts and gaskets?

Click to expand...

I think this is a valid question. I did a quick search as I also have a 2006. Looks like a common issue. Hi squesiton is whether he should replace the manifold or just the bolts and gaskets. I did not find an answer to that.

this was an interesting video.

https://www.youtube.com/watch?v=0yG6WlBNZGI

PerfectReign said:

I think this is a valid question. I did a quick search as I also have a 2006. Looks like a common issue. Hi squesiton is whether he should replace the manifold or just the bolts and gaskets. I did not find an answer to that.

this was an interesting video.

https://www.youtube.com/watch?v=0yG6WlBNZGI

Click to expand...

Thanks Perfect Reign,
Been a member here since 2008 any only post when i need good solid info, good to see a helping hand.Ordered the bolts and gaskets from the dealer and i am going to give it a shot. I have been "goggling" this issue for a while and have seen the videos of people who seem to be trained mechanics doing this. I have a subscription to alldatadiy so that helps.I've done the plugs,wires,belts,shocks,cleaned the throttle body and maf sensor,replaced ac resistor,wired in aux input to my radio, swapped out the clunky upper intermediate shaft, and did the washer on the front cross members .I'm ready to tackle it but was just wondering the kind of problems and solution that i might encounter. I'll take photos when i do it , and if all goes well I'll post them so hopefully others can learn from it. Sorry if peoples feeling were hurt. Mine were not.

I don't know.
I found out I've got three broken bolts and no codes.
Don't know how long they've been broken but I'm sure I hear a faint tapping sound when the engine block is still cold after initial start-up in the morning.
Word of Advise, I never take anything Enoniam says about mechanical issues for granted. After what I've seen he has done in his truck's engine bay, my level of expertise is mediocre in comparison.

i'm going to have to check my engine soon.

i don't get to drive my AV much these days, since I commute in the tiny Jetta.

On all the cars from the 1960s and 1970s that I worked on I never could get those out. Always had to go to a shop and they use a torch to heat the surrounding metal. Heating makes it expand and the bolt hole gets bigger so they are lose and come out.

Aluminum heads are not recommended to be heated to attempt that removal. They do not react to heat the same as cast heads. With any broken bolt the Location, Location, Location makes all the difference as to what you can do to gain access and how easy it will be. If you get the manifolds off and have any of the broken bolt sticking out then you can use a good penetrant over a couple days and even heat just the bolt itself to try and loosen and then when bolt cools can vice grip and try to remove. If it breaks loose then try to work it in and out a little at a time spraying that penetrant in there. Can even use a small ball peen hammer to give the end of bolt a good "whack" to shock it. When and if you do get it out make sure you tap the threads before installing a new bolt.

Hi,
Finally finished with the manifold bolt problem.
took 2 days with one manifold per day. Yeah, it can be time consuming at first.I jacked up the truck and put it on 6 ton jack stands, and removed the tire.
To makes things go faster i removed the plastic wheel wells on both sides.(If you go from the side you can leave the air intake on.)
They are held in with retaining screws. The middle section pops out and then the inner piece comes out after. Most dealers can sell you a bag of 10 for about 5 bucks if you destroy them.
There may be wiring attached on the inside so just keep an eye out and open the clips to release them.
It makes getting to the manifold and bolts so much easier. A generous coating of penetrating oil on both the manifold bolts and bolts attaching it to exhaust system.
Remove your spark plug wires at the plug end and put them up out of the way.
I then went under the truck to disconnect the manifold from the catalytic converters. I'm lucky that i live in an arid region so i get really lucky when it comes to removing bolts without breaking them as they are not corroded too much. First i removed the oxygen sensor, as not to damage it, using a 22 mm wrench.I used a 15mm deep impact socket and patience on the manifold to catalytic converter bolts, as it can take a little time to get them moving.
Once they were off i tackled the manifold bolts. Starting from the front i used a 14 mm socket with extension on each bolt. I closed my eyes and held my breath on each one hoping they were not going to break. The first creak and squeak was music to my ears as the first 5 came out pretty easily.
The last one near the firewall gave me some grief. As soon as i touched the bolt head, it came off in my hand.It broke off right at the head so i was hoping enough was left the to grab.
When i removed the manifold i saw that the bolt was still sticking out a good bit.Luckily i had a bolt extractor wrench that grabbed it easily and it removed without too much trouble.

After cleaning the manifold and engine i reversed the process with new gaskets and bolts, starting from the middle and working my way out equally. The first torque was at 11 pounds and the last pass at 18 pounds.I reattached the pipes, oxygen sensor,connected the spark plug wires, and put back the wheel well. Put the tire back on , and day one was done.

Day two on the drivers side was more the same, with just more wires on the wheel well and less room to work inside. The only problem on this side was a broken bolt near the firewall that was broken inside the engine this time, with no hope of removal by me. It is in an inaccessible place with the firewall curving out there. I couldn't try an easy out there no matter what. I put a new gasket in and new bolts where i could.
I then ordered the kap manifold bracket and attached it today. This in itself was a lesson in patience as there is minimal room to get this done. It took me close to 7 hours to attach it, the bolts dropped from my hands a couple hundred times, and i had to attach it from the top and bottom as there was no way my hand would ever fit between the firewall and engine(even with the heat shield moved).
I again had to remove the oxygen sensor in order to cram my arm up from below to attach the lower bolt. Well that isn't really how it panned out, I eventually attached the top one first, tightened the front bolt so the bracket was in about the right spot for the bottom bolt , then using a pair of long needle nose pliers grasping the bolt and putting it in the hole from below i amazingly caught a thread to get it started. I gently took out the pliers and crammed my arm back up and got it started very slowly by microns. Once i was happy it was going to stay i took my arm out and let the feeling come back into it. I took a 17 mm wrench and using the better part of a half hour tightened it enough so i could put some force on the retaining bolt, over the spot where the manifold bolt would be. Once that was where i thought 25 pounds would be(as i would never get a torque wrench in there)i tightened up the top from the top and the bottom from below. Reattached the oxygen sensor.Dropped the truck.
Again it looks like it went smoothly but it did take 7 hours. My hands were just too big.

Glad you got it fixed.  Sounds like quite a job.  I've never heard of the kap manifold bracket before but I did a search and found a bit of info on it online.