I think I may have a roughness to my engine sound on my 05 GT manual trans.

I was at a light, waiting to take a left turn, and when I took off I decided to show off a bit to a friend and floored it around the turn. I had done that before and been OK, but this time the car fishtailed.

My car was at a 30 degree angle to the centerline of the road, and remained that way for a while! I'm pretty sure I eased up on the gas, and I know I turned the wheel to the right to try to straighten the car out, but it did not straighten. It remained at a 30 degree angle and and continued on down the road that way for what seemed like 10 seconds, but was probably only 3. I think I was in 1st gear and I may have banged the rev limiter for a good 3 seconds. God, I hope it was only 3; I can't be sure, I was watching the road not the tach. I didn't hear any squealing tires. The traction control was ON. I didn't remove my foot off the gas instantly because I was afraid the car would straighten out abruptly and come to a stop, and I was worried somebody behind me would hit me. (fat chance, given the speed at which I took off :') I do remember that the engine was still wound out when I thought it should be reducing in revs.

Anyway, after that, I decided to listen for any anomolies in the engine sound, and I thought I heard a roughness that wasn't there before. Sort of a rotational, vibrational noise. It seemed to happen only when revving it a bit. I was now afraid to rev to the redline anymore lest I damage anything more.

I took it to the dealer and told them that I thought the engine sounded a bit rough. They claimed that they put it on their computer or whatever, and compared it's sound to other 05/06 GT's and it sounded the same. I'm not convinced however. I think the roughness is only there when the engine is cold. And I think that the sound may not be coming from the engine, but somewhere in the drivetrain or transmission. Possibly inflecting a roughness to the sound that the engine makes from the exhaust. Is this possible? Could something have loosened in the drivetrain that doesn't make a mechanical noise, but imparts a roughness to the sound? If they only revved it in neutral, they wouldn't have heard the sound I'm hearing.

I'll try to describe the sound. Instead of the normal brrrrrrRRRRRRRRRRRR! that you'd get, it's more like BrrrrbrrrrbRRRRBRRRRR! With the "b" being a low frequency sound that's not quite the same as the r's.

Am I just hearing something that's always been there and I just never noticed it before? Or could something really be wrong?

I just read about the 3250 vibration problem, and I don't think it's that. My sound seems to happen from 1000-4000rpm. It might happen higher and I just can't hear it over the roar of the engine.

 

the rev limiter is their for a reason, u didn't harm anything. they wouldn't have the limiter if once u hit it, u damaged something. it limits u before u do any damage.

 

But that's to prevent engine damage right? I'm wondering if the high rpm's might haven loosened something in the drivetrain that could wind up as an "engine noise" due to changing stress on the engine. The car wasn't going straight, it was sort of sideways on the road.

It doesn't seem to make the noise if I rev it in neutral. There does seem to be slight vibration associated with it, but as the service tech said when I mentioned the vibration "It's a Mustang, there's gonna be vibration". And he's right. So I can't tell if it's related or not. I'm just wondering about the sound. The engine seemed to roar more before, but maybe I'm just being paranoid.

 

I think your probably worrying too much. After an incident like that, you psychologically want and need to find something wrong. These engines are made to take some performance wear and tear. your revving the engine high on one occasion like that shouldnt do anything. Also revving in nuetral will sound different ofcourse. When your in drive/gear there is a load applied which changes the feel as well as sound of the engine. The noise is probably just your idle/exhuats etc something normal. If your still worried, take it to another dealer, have them drive it, test it, etc and if they tell you its fine; dont worry. If anything goes wrong it would be their fault because they inspected it and failed to find anything wrong. good luck!

 

the only thing i could think of maybe its the fact that you had tcs on. Im no mec, but i think the tcs trys to get traction buy chaning the amout of tq and stuff to the wheels. next time, turn that off.