I have a 1998 Audi A4 Quattro Turbo with intermittent lag in power after starting engine. It starts up with no problem but once the the accelerator is depressed it feels like no fuel is getting into the engine for 3 to 5 seconds (sometimes up to 10 seconds). Once power resumes, the car runs fine until turned off and started up again after sitting a while. This only seems to happen every 3rd start or so - not after every start. The engine light came on after a few days of this and I got it checked out: the fault codes are 16514/P0130 (Oxygen sensor) and 17536/P1128 (Fuel Trim - System too lean). Is this a Mass Airflow Sensor problem?

SOURCE: problems with my 1995 Audi A6 QUATTRO

replace the coil pack, sounds like it is over heating.

SOURCE: 1998 A-6 quattro 2.8L V6 (AHA) I have two codes

PO432= 1 OF THE SENSOR IN THE EXHAUST SYSTEM if u stand in front of engine to your rt under the car should be a oxygen sensor just unplug it and put a new one.....(bank2)
PO441 = Evaporative Purge Flow Monitor check your fuel cap and replace all of your vacuum hoses because they can be damaged or plugged this should fix it.
So good luck to ya....

SOURCE: I am having a problem

I had the same problem with my car, turned out it was the receiver in the ignition barrel (to say it was the right key) that was faulty.
My car would start then stop immediatly, as it would think it was being stolen as it didn't have the right key. Would still start sometimes tho as the imobaliser wasn't working properly.
Hope this helps.