I have a 2001 ford focus,, when its satarts it shakes kind like it wants to turn off,,we already change the sparkplug ,the wires and the pcv,and it make a soud in the moffler..
Maybe a dirty Throttle body, could be your muffler has blockage in it like a flange broke lose could be not letting exhaust flow.
thank u i will tell my husband to check on that....
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