AFC__B5S4

So recently I have been having some car issues, so I decided to give it a good overall tune and service. I recently changed the plugs, I used NGK Platinum. I gaped at .032. The ones in the engine were well over .032, closer to .04 which seemed odd to me. Anyways, I changed the plugs (which is a breeze on the B5 S4 except the two closest to the front of the car...damn IC pipes).

Anyways, after changing them, I now have a rough idle and when I get on the throttle the car bucks like crazy. Anyone have any experience with this? My mechanic happens to be out of town for a bit. I am going to go through and check the coils, but I can't imagine why the car would idling normal and no bucking with the old plugs and all of a sudden new plugs just add to the issues.

The other issue I am having is a boost/vacuum leak somewhere...I think.

Some info on the car:
2001.5 B5 S4
667xx miles
APR ECU and Tune
LLtek Cold Air
Full Borla Exhaust
Hyperboost diverter valves
...the rest are just body or aesthetic mods

I appreciate any help!

speed/efficiency

The plugs are not your problem, Its your air leak. And the reason I know this is because it happens only when on the throttle. Since it happened after your spark plug change I would assume it's your intercooler pipes that removed during it, or if you removed any others, check those too. I have had trouble with the coupler that goes from the y-pipe to the turbo that's right above the two front plugs on each side.

AFC__B5S4

Thanks, I am going to get back in there this week and check over everything and then run a pressure test to help find any other leaks.

internecine

Could be a bad coil pack causing misfires.
I have not had problems with mine yet, but if you search the forums you will find that people say as little as looking at them the wrong way will cause them to go bad. Certainly removing them to change spark plugs jostles them more than looking at them the wrong way.

Got a vag com?

AFC__B5S4

Unfortunately I do not have one, I need to pick one up one of these days. I have never had the use for one as I knew a local mechanic with one, but he is gone...so fixing things are becoming more of an issue.

I am hoping to 'retire' the car and just have it as a weekend driver and pick up something to get me from point A to B as a DD.