Stock 95 S-6 turbo five cylinder with 180,000 miles. It hesitates and surges when try to accelerate but runs ok as just cruise at even speed. Ran three bottles of BG44 to clean injectors and seemed to help initially but then started again. took off injectors and were spraying even pattern. Listened with stethoscope and all clicking about the same. took them out and all spraying same diamond pattern. replaced fuel filter. replaced plugs with Bosch from dealer. replaced connectors between coils and plugs. put on a new charger or activator that fires coils ( on firewall and plugs into 3 coils per activator) and made no improvement. Took to Audi dealer who charged $125 for diagnostic but he found no solution to the problem. Help would appreciate any suggestions of what else could be causing this problem.