LF help diagnosing code 4530 underboost on 35D

[Chips]

Bought this 2012 X5 35d (US) wholesale from a dealer after it had gone through 2 BMW dealer service departments and failed to make it to a front lot. Last one claimed was a failed small turbo. Really not sure what to try next I've already put enough time into it and I'm an amateur so roast away my order of operations. Been chasing this for months!

Only thing that stands out to me was the electric valve on the EGR cooler, brand VEMO, German made, stamped 2021, had failed due to leaking vacuum. Replaced valve gets really hot with just current flowing (key position 1) but no codes is this normal?

Used all new BMW/OE parts less silicone vac & CCV hose. Verified no vac lines kinked. Only original code was 4530 and it still persists: Charging pressure control, high pressure stage, control deviation:charging pressure too low / positive control deviation.

Here are all my notes and the latest test drive fault read. Latest drive had most number of faults and at highest frequency after replacing the failed electric valve on EGR which I'm not sure if I missed it earlier or if it just failed.

Factory 4530 Service Measures & Results/Notes
1. Check air mass system for leaks. - - replaced CCV hose, every rubber vac line, air intake seal
2. Check exhaust system before turbines for leaks
(Internal leaks possible at joint between large exhaust turbocharger and exhaust manifold at seal for turbine control flap.) - - n/a (no smoke machine available)
3. Check EGR valve.- - CBU removed, no leaks
4. Check throttle valve (fault entry) - - CBU removed, no leaks
5. Check turbine control flap - - moves freely, opens with proper vacuum, no leaks
6. Check charging pressure actuator, high-pressure stage - - joints move freely, opens with proper vacuum, no leaks
7. Check high pressure stage of exhaust turbocharger for damage on compressor wheel and turbine wheel - - replaced high pressure turbo/gasket, all turbo oil lines (no cokeing on old lines)
8. Check wastegate valve - - moves freely, opens with proper vacuum, no leaks
9. Check intake ports and intake valves for sooting
(Excessive oil entry from the crankcase ventilation can cause sooting, especially in the event of short-distance driving - - ports/valves clean (borecope inspected), intake manifold/swirl flap/EGR/throttle CBU removed, replaced all gaskets

Also replaced trying to fix 4530: x3 electric switchover valves, x3 pressure converters, EGR/intake/throttle gaskets. Replaced too the thermostat, air filters & heater water valve (non-functional). Dealer replaced last 2 years/10k miles: SCR active reservoir, up/downstream NOx sensors, MAF sensor.

[robinasu]

What about the motor mounts? They have vacuum control.

Also, just spit balling, but have you double checked the MAP sensor to see if it's seated correctly and not plugged with CBU? Sounds like you've been all over the engine.

Do you have ISTA+?

[VW TDI X5 Convert]

I'm at the same point with my 2011 x5 35d.

I have code 4530, 3FF0, 4865.

I've replaced all the vacuum lines and pressure converters and EL valve.

Everything holds vacuum. Checked my motor mounts and they hold vacuum.

Cleaned MAF and MAP

Plenty of boost off the line with no smoke.

EGR, DPF, and ad blue deleted.

Keeps going into limp mode at about 30 MPH

Cleaned Intake manifold and removed valve cover and cleaned. The intake valves looked good. No CBU

[Chips]

I'm buying a pressure test adapter and a smoke + pressure machine to diagnose boost and intake leaks. In retrospect, I should have purchased these sooner as the parts bill is really starting to add up! I'll report back with results in the next couple weeks.

[VW TDI X5 Convert]

I'm just like you I bought the car from a mechanic that couldn't fix it for a customer and they couldn't come to an agreement on who was responsible. The car has alot of parts that where thrown at it. The mechanic was a duramax diesel guy and not a BMW guy. I'm like you I'm an amateur.

I've been working on mine for a few months as well. Plenty of boost off the line. I did a swirl flap delete and replaced all the gaskets on the intake manifold when I was in there.

The mechanic said he smoke tested everything, but I guess I'm going to get a smoke tester myself. I'm like you at a total loss and replaced all the normal things that seem to fix the problem but to no avail. Hopefully somebody will chime in. I bought a top of the line FOXWELL scanner but no ITSA.

[Rondo]

hi my 2012 with dpf and egr delete has the same symptoms and i found that the intake manifold has a crack on the driverside that is leaking oil and also boost .I will replace this week and see if that is the only problem .

[VW TDI X5 Convert]

Originally Posted by Chips

I'm buying a pressure test adapter and a smoke + pressure machine to diagnose boost and intake leaks. In retrospect, I should have purchased these sooner as the parts bill is really starting to add up! I'll report back with results in the next couple weeks.

Here is a few PIDs from mine

[Chips]

Just following up to say that I solved this. Ended up doing valve cover gasket and tracing all the wiring to that hot switchover valve. Neither of those ended up being the issue.

It ended up being an issue with the vacuum actuated turbo switchover valve. There is a rod clearly visible below the exhaust manifold and mine was adjusted far too high. This caused the wastegate valve to remain open causing code 4530.

I adjusted both nuts down from about 30 threads showing (below the lower nut) to 17 based on information I got on other forums.

[robinasu]

Awesome resolution and feedback!

[VW TDI X5 Convert]

Good to hear you solved it