i have an 08 csrt4 the only mods is a muffler delete and a bop the local dealer jus put a brand new oem turbo wastegate map sensor and 2 solenoids on the air box and when it hits 4 grand in 3rd gear it starts sputterin and makin fluttering noise and has like a dead spot in the power thet have been workin on the car for a month and they cant figure it out any ideas please anyone

 

Running out of fuel perhaps? Fuel pump not keeping up under heavy load.