My 2005 mustang GT is having strange problems. The car has a weird idle thump when stopped and parked. I can feel it in the cab and also out the exhaust. brought it to my tuner he said its not misfiring or anything. I cleaned my TB and MAF sensor still having problems. the car stutters when taking off and slowly accelerating. Im lost and dont know what to do. There are no codes showing or anything. Almost feels like i have bad gas. Help is appreciated

 

Is it all stock? When did this start happening or has it always done it? If you have checked all of the mechanical stuff it sounds like it could need some more tuning.

 

I have cold air intake . I had a BBK throttle body but my tuner basically told me it was crapped out so I took it off & had them retune back for my stock tb. It happened about a week ago. I have no check engine light. Not sure on how to check for vacuum leaks it could be that.