Hey all, recently had quite the scare in my ‘87 camaro. its always had trouble starting since i bought it but this time was different. it got close to turning over and then BANG - smoke was flowing out of the back of my car and i thought i had died. I hopped out and checked out the rear end to see a hole about the size of two baseballs had been blown out of my muffler. What would have caused this? I think it is a clogged cat, which would also explain the hesitation when accelerating and rough idle, right? Well, for now i sawed off the exhaust, and the car still runs a bit rough but at least it moves. Any ideas on what caused this and what I can do to fix it are appreciated, thanks!

 

Mufflers explode when they get filled with raw unburned gas , that builds up till the boom . For whatever reason , your engine is putting unburnt fuel into the exhaust (too many possible reasons for this to list) . It really could be anything from a minor tune up (bad sparkplug ?) to a cylinder lacking compression (new engine time ?) , , , and anything in between .

And for the love of God man , get a flippin exhaust system back on that car before ya go getting us ALL branded as knuckle dragging malletheads

 

A clogged cat will not cause a muffler to explode.

What WILL cause that, is loads of unburned fuel accumulating in it by it being put through the motor while it won't start, then getting set on fire by the first cylinder that finally fires.

You have an ignition type of problem, preventing it from starting easily.

Try a new set of spark plugs, and a dist cap & rotor.

And of course, a new muffler...

 

Apparently you have one of those fancy external combustion engines.

 

Nearly spit soda all over my keyboard...

 

Id tune it up first thing first,, cut off that useless cat, and put a new muffler in there.