Rotor burnt.
Wires bad.
Fuel pressure fluctuations.
Electrical fault in engine wire loom.
Bad OVPR.
Faulty Fuel Distributor.
Sticky Air Flap Piston.
Acceleration enrichment module failing.
Bad engine ground.
A/C ripple from alternator.
Ignition switch faulty.
Any, or combination of above.

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[http://languageandgrammar.com/2008/01/14/youve-got-problems-not-issues/ ]

"A liberal is someone who feels they owe a great debt to their fellow man, which debt he proposes to pay off with your money."