My car is giving me these codes hope someone can help me
PO300: Random/Multiple cylinder misfire detected
PO301 Cylinder 1 misfire detected.
PO303 Cylinder 2 misfire detected.
PO303 Cylinder 3 misfire detected.
PO304 Cylinder 4 misfire detected.
PO411 Secondary air injection system incorrect flow detected.
PO507 Idle air control system rpm higher then expected.
My friend advise me to change the idle air control module (throttle body)

I'm guessing either the spark plugs are out or your coilpacks are out (I'm about 80% sure on the latter since our cars our known for this problem).

Try posting this in the B6 A4 forums. You might get more answers there. But I'm with Randall on this one; it's probably coil packs.

thank you so much guys. i did verify the coil packs and they r good took out the spark plugs and they r burning fine maybe running rich right now.

my friend told it could be the mass air flow censor or the throttle body.

Did you touch those 2 things recently?

They are fairly "fragile" so it's a possibility that those are the problems. I guess try cleaning them first to see if those are the causes - be really careful tho.

i'm leaning more towards the MAF...

I had same issue and turned out to be bad coils and plugs and vac leak. With engine cold spray carb cleaner around engine. If your idle changes you have a vac leak.

Why haven't one of teh mods or admins moved this thread to a more appropriate sub-forum, yet?

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