Turbo problems

[Accord_Zero]

I just got finished turbocharging my 1996 Honda Accord. This was a custom turbo setup, with different parts from different companies. I'm hoping someone here can help me label these problems...I'll list them:

1. The idle is fine when I start the car and let it sit. Also if I drive it very slowly and come to a stop, it'll still be ok. But after a few seconds, the turbo will spool up while driving (extremely loud...sounds like a jet engine), but after I let off the gas and come to a stop, the idle is extremely low...to the point where it's just about 0. I have an automatic, so it shouldn't stall if I keep it in gear, but is there a way I can fix this? Why does it only happen after boosting?

2. A loud clanging sound coming from the area of the valve cover can be heard every now and then, especially if it's parked. This only happens once the idle goes down a lot (after the computer is messing with it). But it almost sounds like something is in the valve cover bouncing around...I highly doubt we dropped anything in there...the only thing open was the oil cover, and I watched that thing like a hawk. Any ideas on what that sound is? It's very inconsistent and more noticeable while the car is stopped.

3. And one last thing is just a question about the wastegate. It's an external and open wastegate (haven't gotten a dump tube yet), and there's a loud exhaust sound coming from where it is once I start boosting. Is the exhaust sound just the wastegate opening?

Another thing I should mention is that my fuel system has not been upgraded...should I get a fuel pressure regulator? I have an FMU.

Sorry this is so long, but I figured I'd ask all the questions at once. I appreciate any help you guys can provide.

[whtteg]

I will take a stab at it: did you use anything like a missinglink in the car when you decided to go turbo? It kinda sounds like the ecu is detecting the boost and going into safe mode.
And I would upgade the fuel pump to be safe.

[Accord_Zero]

I have the missing link on there. I drove it again tonight for awhile and I noticed my air/fuel gauge is working...but it's showing it to be extremely lean...it only lights up the first notch of the lean zone. So I'm thinking the FMU isn't working, or that it's installed incorrectly. I will mess with that tomorrow...but it seems I'm way too lean right now. That would explain a few things.

However, there's a new noise I'm concerened with...and that would be a horn-sounding noise (like a musical instrument horn)...or the sound of plumbing when pipes squeal. Again, it's inconsistent and will stop when I apply gas. I heard that a kazoo kind of sound means a turbo is bad? Is this true? Not sure if this would be classified as that though.

[Accord_Zero]

I've been reading about the Missing Link after you mentioned it...is it possible that I installed it upside down? Would that make a difference? 'Cause it seems that could be a reason my idle is so bad...the engine performs a little inconsistently, but only after it detects boost.