car has been sitting for a month, got the timing belt, water pump, alternator/power steering belts changed and wheel bearing and motor mount. it needs one more motor mount BUT after getting it back it now misfires. i checked timing and coils, and spark plugs for spark but (didn't check galling) and for a vacuum leak and nothing. there is no engine code being throw either. could it simply be bad gas? it rode fine before it went into the shop and on the way home but now it misfires. the vibration at idle is for bad motor mount i'm thinking. could a bad motor mount cause that? HELP
My car has 170000 miles.
Hi there. When a vehicle sits for more than a few weeks without use, it is very possible that the gasoline could be a source of your engine misfiring problem. When gasoline sits, the carbon molecules that are separated during the refining process begin to collect together, creating larger chain molecules that are harder to ignite in the combustion chamber. However, it’s also possible that one of the fuel injectors themselves are clogged with excessive carbon build-up or misfiring. It might be a good idea to have a professional mobile mechanic come to your location and complete a engine is misfiring inspection.
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