B6 From Hell

[SweeetBabyJames]

Purchased my 2003 A4 3.0 (currently has 55K miles) a few months ago.

I recently started smelling gas in the cabin and was able to pin-point the culprit: a cracked level sensor housing. A new housing has been ordered from ECS and I'll be replacing soon - hopefully correcting the gas smell.

As of today 8.25.2016 my A4 has started to vibrate strongly at idle and acceleration but slows and almost quits at a coast (clutch in). CEL is not lit so i don't think the coilpacks are to blame. I've been reading that this could be either a motor mount or the flywheel. My question to everyone is:

How would i diagnose if the vibration is coming from either the flywheel or motor mount?

Thanks!

[JDillon15]

Just because the CEL isn't lit doesn't run out the coilpacks. You should still get a vagcom and make sure there are no "soft codes". That should be stop #1.

[SweeetBabyJames]

Update:
I've changed the coil packs and plugs as recommended and the vibration has gotten worse.

The vibrations is vey audible when the clutch is compressed but not when the clutch is out.

Also: I am now throwing a code P0356 infinitive coil..' :|

[jpulll]

what type of coils? OEM for b6 or red top fsi coils. what plugs? what are the plugs gapped at?

[old guy]

P0356 AUDI - Ignition Coil 6 Primary/Secondary Circuit

Possible causes
- Faulty Ignition Coil 6
- Ignition Coil 6 harness is open or shorted
- Ignition Coil 6 circuit poor electrical connection
- Faulty Engine Control Module (ECM)

When is the code detected?
Each ignition circuit is continuously monitored by the Engine Control Module (ECM). The test fails when the ECM does not receive a valid pulse signal from the ignition coil.

Possible symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Lack/Loss of Power - Engine may be harder to start
- Engine hesitation
- Rough engine idle

P0356 Audi Description
The ignition system on the vehicle uses individual ignition coils for each cylinder. The Engine Control Module (ECM) controls each ignition coil operation. The ECM sends a ON/OFF signal to energize the ignition coil to create a spark at the spark plug when a spark is required at the cylinder.

Check your wiring harness and connection to the #6 coil pack.