Re: Exhaust manifold leak...broken bolts?
Your best bet to identify any exhaust leaks is to go to a shop that services a vehicles air conditioners system. They will have a smoke machine that they use to identify leaks in the AC system. This can also be used to smoke the exhaust system.
The smoke they use will leave a florescent dye that can be seen when using an inspection light. This will find any and all exhaust leaks you may have.
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