I had my water pump blow and replaced. After the car was returned I have a flashing CEL. The shop wont take the car back as they say it was "working fine when we gave it to you..."

Car: 2002 A4 3.0 V6 Quattro.

So I have misfires on Cyls. 3, 4, and 5. The car flashes the CEL only when at low to mid throttle position between 1500 and 3000 rpm. If I use WOT the cel will quit flashing (stay solid). anly codes are the P0304-P0306. Is there some sensor or vacuum tube that would be disconnected during a timing job that the shop maybe didn't re-connect. I checked the plugs and coils and they are all good.

Any ideas?

Thanks

Will