My 2011 A4 started stuttering ,engine shaking badly the check engine was flashing they stayed steady. it did that while i was driving. next morning it was the same. Drove it to the mechanic who said my spark plugs were very old and had oil on them. changed all 4 spark plugs and the 2 coils that were bad. The stutter came back on but only in the morning when the car is cold, once i start driving its no there but acceleration is weak. the computer is reading the following codes : p227900 intake air system leak , p119a00 fuel pressure sensor g247 malfunction, p050600 idle control system RPM lower than expected, p030300 , p030400, p030200, p030000 cylinder 3, 4,2,1 misfire and also p030000 random/multiple cylinder misfire. The dealer is telling me we need ot start by replacing the vacuum pump and upper timing cover gasket since both leaking very little oil . Other mechanic is telling me its your timing belt. cleared the codes a few times and the codes still came back.