Weird Noise

[antigravity]

As per my sig, I've got a BA and I've got a weird little problem.

Before and after my tune, I've noticed a weird sound under boost at highish RPM (say 4000rpm+)

It basically sounds like this "ftftftftftftftftftft" sorta like some boost or something is leaking on and off and on really quickly. I've also noticed after 4000rpm I lose a lot of torque, and the power seems to die off until it shifts to the next gear under 4000rpm.

Initially I thought it was an exhaust manifold leak, but I've tightened all those bolts like you wouldn't believe and its still there. All the hoses are tight, I can't see any splits in any of the hose joiners (ie at the turbo inlet) and its starting to drive me nuts.

Its not my plugs, because I've got brand new .8mm plugs and the noise existed before I changed them. All my coils seem to be working at idle too...

I'll try and record the noise, but its not overly loud so it might not be recordable as I'm driving.

Does anyone have ANY idea? Its getting to the point where I'm stopping myself driving the car hard (which is the point of having these things!)

Cheers

Dave

Edited 24/08/08 04:14 AM by antigravity

[ETM]

Check the turbo- manifold join and also the rear housing-turbo core joints.

Nuts and bolts commonly fall out in these areas

[antigravity]

What is the best way to get to these? From underneath?

[antigravity]

Here are some videos... Unfortunately you can't really hear it... Its almost like a spitting noise if someone was going 'tftftftftftftftftf' and spitting as there were making that noise. If that makes sense!

(Click on the images... couldnt work out how to have the videos direct on the page)

[ETM]

What is the best way to get to these? From underneath?

take off all the heat shielding and get to it from the top

[Iconic Bionic]

http://www.fordxr6turbo.com/forum/index.php?showtopic=48951

Good summary here of how to check and tighten all of the bolts in that area. I asked the question only yesterday after finding one of the manifold bolts really loose.

I.B.

[antigravity]

Thanks for the link...

I don't have a heatshield anyway... Ripped it off a long time ago. I'm trying to find some photo's on here on which bolts I need to tighten.

I've tightened all the manifold/engine bolts. But not the bolts to turbo. Every time I've checked them, they've been ok.

[senna_T]

Check the bolts on the exhaust side of the turbo itself, they come loose pretty easy, plus the dump pipe bolts

[Blacktigerlight]

Did you have any luck? I have exactly the same problem and it's driving me nuts. Originally thought it was manifold bolts but after being tightened it hasn't helped. Haven't been able to flog it in 6 months! Any help would be awesome.