Originally Posted by Gugs
Where do you read the word Always in my sentence BMWD?
You didn't. But I posted that to let anyone else reading know that you can have wastegate problems without hearing any of the typical wastegate rattling noises. Just relaying what I've personally seen.
Originally Posted by Sparky68
Thanks for your input.
What would be your plan of attack on my issue? I am going to log map 4 tomorrow [as suggested by one of the forum members] after that if it does turn out to be a leak which i think is possible, [it has been suggested the JB4 is faulty] should i just get it smoke tested?
I mean, it could be a lot of things. I've personally never seen a boost leak on an N54 car that wasn't caused by someone leaving something loose. If the car has aftermarket intercooler, charge pipe, etc. , then that's another story. I've never seen a stock bypass-valve leak, but I know it can happen when the boost is raised. Keep in mind I mostly deal with the OEM stuff professionally. What have you done as far as mods?
9 out of 10 times I see a car with 30FF come in (and no other related faults), it is usually a vacuum control type issue or a wastegate issue. Could be something as simple as a torn vacuum line near the EPDW valves. I'd check all those lines over very carefully.
If you have a vacuum pump (Mity-vac) you can test both the EPDWs for leakage. This is something that I've seen a number of times, and will cause the 30FF fault. If you have that vacuum pump, It's really easy to test. Just see if the inlet side (port that the vacuum reservoir line connects to) of the valve holds a vacuum with the engine off. These valves are sprung closed and should hold a vacuum. If it doesn't, that's a problem. There is a seperate valve for each turbo, but the outlet sides of the valves are T'd together. So if 1 valve is leaking, it will affect both turbos. You'd still have some boost, but the wategates aren't going to do what the DME wants them to.
If your charge air system is stock, I'd definitely start with the vacuum control part of the system. If you've changed things and there is a chance you've introduced a leak, then you may want to start there. In that case, a smoke test could be a good option. Hope that helps.