dastangman

Well, the car is a 2001 Mustang Cobra, has a fresh forged rebuild with 300 miles on it. The question I have is a noise I began hearing tonight that I don't remember, as a matter of fact, it may have always been there but I actually had the radio down.

The noise is hard to explain, but it's similar to an egg beater that you just crank. Not really a click, not really a static, but not really a buzz, kinda somewhere in between those three. I was going to post a video sound clip, but my camera ended up saying it couldn't take a video (I'm guessing because of battery).

The most prominent times the noise happens is in 5th gear, 55 mph and you just lightly tap the accelerator. If you press a little harder the noise seems to go away. It also happens sometimes when just getting moving, like as I press the accelerator in 1st gear it'll start to make the noise, press it harder and it goes away. Same for second, but none are quite as noisy as 5th.

The noise goes away when I release the gas, doesn't make any noise at idle when revving. If it does it's so light you can hardly hear it. It's not a super loud noise, but enough that with the radio off you can hear it and it'll drive you nuts.

To be honest, I'm not sure what the viscosity of the oil is right now, as it was actually the last thing on my mind when I picked the car up from the builder, but I've been told I need a higher viscosity oil. That said, with just now 300 miles on the new engine, what do you recommend changing to for oil, when, and could this be related?

Thanks for the help...

MU71L4710N

exhaust leak?

dastangman

No, I would highly doubt that, but I haven't necessarily ruled it out. I used to get an exhaust leak out the headers every once in awhile, but I just had the headers reinstalled with Stage 8 Locking Header bolts when they finished rebuilding the engine, and the sound just doesn't click like an exhaust leak does. Plus, the conditions it happens under just don't seem to fit with my previous exhaust leaks. That and I can't really hear the ticking of an exhaust leak while on the outside of the car.

I'm going to take it to the exhaust shop soon, just to make sure, but this just doesn't sound like that. Thanks tho, that was my first thought too. I'll keep ya posted. It needs an oil change soon, so I might bump up to something a bit thicker...input?