racpace

I have a mysterious sound, like an exhaust leak coming from the engine that only happens when the ening is under a load. Then after the motor warms up it gets alot quiter. I had the exhaust checked out, no leaks. It has BBK shorties installed. Driving me freakin crazy. Any ideas?

MJH78

what does an exhaust leak sound like? I really don't know. anyways, I had a buzzing/rattling type noise when I got my car at like the 2k rpm mark, and only at that rpm. When I got my catback installed, it got a little louder. I figure it's an exhaust hanger or something else loose down there, but I really have no idea. And mine is also only when the engine is under load. It's like a "metallicky" sound. is your similar?

racpace

It's more of a high pressure sound, like a header leak. But it starts loud when the engine is cold, then gradually gets quieter as the engine warms up. I didn't know if the EGR valve could ever give off a sound if it's failed. It is like I said a header leak or some sort of high pressure leak type of sound.

mestit3

MJH78, mine does the exact same thing it only does it when you are accelerating and it is only for a half second at about 2k and when it gets warm it goes away. very annoying

hpwrestler220

+3!!!! i fvckin hate it

MJH78

The other day here it was like 80+ degrees, and it did it even more with it being that warm outside so something tells me it's just something loose under the car. when it gets hot outside of course things tend to loosen up a bit.

racpace

I think it's the EGR, or loose header bolts. It's gonna suck tryin to tighten those SOB's! I'll let you know if this fixes it.

CobraStangGT16

a metallic rattling under load is a loose cat converter if you have them. mine had that for a month.

but other than that, it could be a faulty gasket.

poison2986

It could be aRod Knock. My truck, F-150,does that when its cold out but when the motor temp. get warmer it goes away and i've got the 5.0L engine in it....

mestit3

i played around with it a little bit today on my way to work. if i accelerate very slowly, and find the right rpm between 17 and 1800 i can hold it there and make it do it until i speed up or slow down maybe 1mph. if i take off pretty quick it will last half second at most just as im passing that 'magical' rpm