I recently installed a MAC CAI on my '03 Stang. Now when i turn the ignition, there is a thump coming from what seems to be the passanger's side under the hood. I cannot figure out what is causing the thump. Has anyone heard of a problem like this occurring after CAI installation? If not, what should i do?

 

is this thump only when you turn the car on? did you go over the instructions and make sure everything was put on correctly? if that does not work put on the stock air box, if you still have it, and crank the car to see if it thunks, if it does it might not be the intake, if it does not put the intake back on and listen for the thunk when you crank it.

 

the thump is only when i turn on the ignition, everything else seems to be fine. i would really rather not put the stock air box back in, so if anyone has any other ideas, that would be great.

 

honestly i would not want to put the stock air box on again. i did some more thinking on this and only two possibilities hit me. one is where the intake and MAF meet it might not be tight, there are 4 bolts there and the lower passenger one is a pain in the ***. two where the intake goes into the fender might not be tight.