Q: CAT got clogged, backfire and nowturns over but no start and gas smell

asked by on February 12, 2017

I was traveling about 50 mph and noticed a slight sputter.. went away for a few seconds and then started to sputter even worse when applying gas.... and then BANG!!! sounded like a gigantic backfire is all i can assume it was but as soon as the bang it died. i pulled over and cranked it for a minute, it started after a few tries but died immediately. There was a strong sulfur smell and sure enough it appeared the cat was clogged so i cut it out to see if i could start back up. No good, just and extreme gas smell and turning over. What do i do now??

My car has 190000 miles.
My car has an automatic transmission.

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In most cases, the ’bang’ you hear is an explosion of excessive carbon inside the cat itself and more often than not stays contained inside the catalytic converter or expelled out the muffler tail pipe. In some cases however, it may damage ignition system components, sensors, cylinder head hardware or worse, piston connecting rods. I would start by having a professional mechanic come to your location and complete a car will not start inspection; as they will be able to provide better direction after inspecting your Blazer.

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