[TrollToll]

Chasing a 30FF code and I've replaced all vacuum lines and pressure tested the system. I don't have any wastegate rattle (other than half a second on startup), is it possible that my wastegate actuators are out of adjustment and not closing fully without producing a rattle? My car is very slow to build boost and is consistently 2-3 psi below target, whether target is 8 or 15,it's always a little low.

[Sgop335]

Perhaps boost solenoids. How many miles?

[TrollToll]

91,000. I haven't tested the solenoids yet. I have a syringe coming in an mail to test the actuators and need to pick up a vacuum gauge to test the solenoids.

[Briancanadiano]

Could be clogged secondary cats

[jwebb335xi]

Originally Posted by Yournamehere90

Chasing a 30FF code and I've replaced all vacuum lines and pressure tested the system. I don't have any wastegate rattle (other than half a second on startup), is it possible that my wastegate actuators are out of adjustment and not closing fully without producing a rattle? My car is very slow to build boost and is consistently 2-3 psi below target, whether target is 8 or 15,it's always a little low.

I chased the same code. I replaced vacuum lines, boost solenoids (one sounded like a duck call under high boost), and double clamped connections into and out of FMIC as well as charge pipe. All good for several months and a day at the strip since.

What about your diverter valves; stock or after market?

[TrollToll]

Originally Posted by jwebb335xi

I chased the same code. I replaced vacuum lines, boost solenoids (one sounded like a duck call under high boost), and double clamped connections into and out of FMIC as well as charge pipe. All good for several months and a day at the strip since.

What about your diverter valves; stock or after market?

Stock diverter valves but I tested them up to 20psi. They leak, but only a tiny bit. Nowhere near enough to cause the issue. I've checked Fmic connections as well. Next step will be boost solenoids (swapped from my 135i as I know they're good), and I'm wondering about the cats. I wish there was a way to monitor back pressure

[jwebb335xi]

Originally Posted by Yournamehere90

Stock diverter valves but I tested them up to 20psi. They leak, but only a tiny bit. Nowhere near enough to cause the issue. I've checked Fmic connections as well. Next step will be boost solenoids (swapped from my 135i as I know they're good), and I'm wondering about the cats. I wish there was a way to monitor back pressure

Inlet connections, charge-pipe to throttle body O ring..... Can't think of much else. A smoke test may make sense.

[TrollToll]

A little update. I used a vacuum pump today and am getting 25 in hg at idle, I pulled vacuum on both wastegates and they hold it fine, the rear rod moves but I couldn't see the front. There is no rattle. I teed into the lines going to the wastegates and they get about 20 in hg under load. It fluctuates wildly but I assume that is normal. When I shift to 6th and accelerate it holds steady at 20. I would assume that if my turbos are capable of 14 psi then I shouldn't get this problem on stock tune, but I do. I'll try another round of leak testing, but I didn't find much last time.

[BeeMuh]

The last time I had this issue was my jb4 G5 required a software update, inter cooler was loose and needed new vacuum lines.