I have a 2005 Mustang GT 5spd with 19'000 miles on it. Third owner with only some Flowmaster axle back exhaust and a cold air intake. It ran perfect for the first 1000 miles I had it. Now there seems to be some kid of noticeable power loss. Its almost like I'm not letting off the clutch all the way and it's not getting full power. I'll put it to the floor and it hardly picks up. But other times I'll give it full throttle and it put me back and takes off. It seems to be getting worse and I was wondering if anyone has experienced the same problem and if they know what it is or how to fix.

 

This could be a myriad of things. Easiest thing first: disable the TCS and see if you still feel a power loss. 2nd, does your CAI require a tune and if so, what/ who's tune are you running? A no-tune-required CAI could still cause performance issues but usually will also throw a code. Next, try cleaning the TB and run a tank or 2 of a proper SeaFoam mix.

 

Ill give all these a try. And The CAI doesn't have a tune that I know of. The best I can describe it, would be me putting peddle to the floor and only getting the power that you would if it was half way or just a little more than that. There is actually points where I start to accelerate and I can feel loss of power and then it'll suddenly kick in an pick up like normal.

 

air filter? fuel filter?

 

The air filter is pretty clean, but I'll clean it just to be sure. And I guess I'll just have to change the fuel filter since there isn't really a way to check that. Lol.
What about the TPS sensor? I'm gonna hook it to a computer tomorrow.

 

Air filter? fuel filter? No.
Drive by wire systems can act up a bit. You have an electronic pedal, and an electrically operated throttle body, with an ECU in between. ECU's rarely go bad but gas pedal assemblies have been replaced many times. You can google, or search this site for what the pedal assembly looks like and how it works. Could easily be your problem.

 

That's what I was thinking. I thought the throttle positioning sensor went bad.

 

What CAI are you running?

 

Just a regular K&November with plastic tubing. It was there when I got the car. I was gonna switch it to Air raid with a tune.

 

I don't believe there is a tune now.