Silver_Stang_05

Lately my Mustang feels as though it's lost some of it's power. When accelerating through 2nd, 3rd, 4th the engine sounds as though it's "racing" but yet the performance isn't there. Used to be in first if I was doing about 10-15 and stomped the gas I would get wheel spin, now i have to pop the clutch to get that. Not that I'm running around town burning up my tires, but I would like to have the option to do it if I felt like it.

It's an 05 Roush Stage 1 with 16,500 miles (yes, that's correct), K&N intake, gutted cats and Pypes X-Pipe. Run nothing but 93 octane, air filter was cleaned 3 weeks ago with oil change. Also, in the mornings when it's cold I get a nice loud rumble at idle, after warning up it becomes quiet, you can't here rumble from the front of the car??

Any thoughts as to what could cause this?

07VistaChicago

I think I can answer the question about the rumble, but not the power loss. These cars start up with retarded timing so they start easier which makes them louder (the firing of the cylinders is closer to the exhaust valve opening timing). After a couple 10's of seconds they return to normal timing and become quieter.

Power loss, maybe fuel filter? Check a plug or two and see how they look.

Silver_Stang_05

Damn, fuel filter......can't believe I haven't checked that yet.

Thanks for the info on the startup, explains it, but it sure does sound better in the mornings!

moosestang

I noticed the timing starts out at zero, but didn't know it effects the exhaust sound.

Silver_Stang_05

Yep, it's noticeably louder when starting cold.

lawrencecar1

dirty maf ??