What's that noise?!

[oneturbo]

I was on my way home a few nights ago and decided to boost it a little in second. out of nowhere it started to make a noise, like a metal,rattling kind of noise. kind of like the sound it made when you where a kid and put a can on your bikes' tire to make it sound like a motorcycle? i thought maybe it was the turbo. But when i first got the car the guy before me had blown the turbo and thats how i bought it. it didnt sound like this, and it smoked like crazy out the back. its not doing that since the noise started. could it be something with the exhaust? Please someone help me with some suggestions!

[turbovanman²]

What car? what trans?

Have you done a compression test? does it still run smoothly? Any guages? Whats your idle vacuum?

[Big_P]

Detonation?

[oneturbo]

its a 2.2 1990 shelby. manual trans. it does seem to get full power and it doesn't seem to be bogging down at all. the noise is always there. as soon as i turn it on you can hear it. when i drive it it seems to get louder as i accelerate, but whenever i shift it goes back down. i am getting a little white smoke out the back. i haven't done any kind of official tests, but i did listen to see if i could hear exactly where it is coming from. it seems to be coming from around where the intake manifold, turbo and exhaust all are connected. i dont really get any rough idling and my overall oil pressure is staying really high.

[oneturbo]

my vaccum stays pretty steady at around 15.

[turbovanman²]

15 is a bit low, you could have popped the head gasket. I would do a compression test. Maybe post up a vid.

[oneturbo]

ill try to get a vid of it up by tomorrow. so, can i pretty much rule out the turbo? cause i don't want to replace that thing again. especially with how expensive those vnt's are! what are some other symptoms of a blown hgasket?

[shelbydave]

Possibly the Catalytic converter rattling?

[thefitisgay]

i bet its the aluminum heat sheild on the firewall or one of the lines that runs behind it

[oneturbo]

yeah i was thinking that maybe it might be the cat, or something with the exhaust. cause i notice that when i'm driving the noise gets deeper and higher depending on the rpms. ill check it.