I think the most important thing here is the 4530 error code - it's a very generic error code that indicates your boost control isn't working and the boost level is too low when high boost is called for.
From a BMW TIS on error 4530: -
4530 - Charge air pressure control, control deviation, charge–air pressure too low.
CORRECTION
The possible causes for the induction undercharge/overcharge faults are:
Charged air leakage between the turbochargers and the intake manifold;
Air filter or air path before turbocharger clogged;
Incorrect operation of turbochargers actuators (low vacuum supply for VNT actuator, etc.);
Intake manifold pressure sensor malfunction;
Excessive backpressure in the exhaust system.
There's a few things in there to consider. The vacuum hoses are a good place to start, especially around the turbo and vacuum reservoir on the right side.
BTW, the manifold and fuel pressure values you gave above look ok - as far as I can tell from a static value. It would be more useful to see how these vary over time (at idle).
But coming back to your 4530 error, you may need to get a small vacuum gauge test set to diagnose this further, as there are multiple vacuum lines and components that can cause this state/error.
I use a $30 vacuum tester to check mine (after replacing the exhaust manifold in this case): -
http://i66.tinypic.com/5cx3ia.jpg
In this picture, I'm testing the turbo actuator directly, to ensure the correct movement and travel distance of the actuator are (and therefore the VNT vanes in the turbo. You can also use this tool to test lines, the reservoir and the pressure modulator.
The pressure modulator is high on my list of "suspects" in your fault but I think you may need to systematically eliminate all the possible causes....
Here's the info. on the boost control: -
https://www.newtis.info/tisv2/a/en/e...tuator/XN2m7mn
and the boost pressure sensor: -
https://www.newtis.info/tisv2/a/en/e...sensor/XWfcH87
Air-mass system tests: -
https://www.newtis.info/tisv2/a/en/e...m-test/XZFEclB
(BTW, there's a line in here I've been looking to find for a long while now - something to indicate that NO X5 E53 ever had swirl flaps - the TIS reads...
Component groups of the air mass system
The air mass system consists of:
- Charge-air-pressure sensor
- Intake Air Temperature Sensor
- Air-mass flow sensor
- The exhaust-gas recirculation controller comprises the EGR valve, pressure transducer, pneumatic and electrical activation of the pressure transducer
- The charge-air pressure actuator comprises the turbocharger with adjustment, pressure transducer, pneumatic and electrical activation of the pressure transducer
- Swirl flaps (in all series except for X5), in cars as of 03/2000 with automatic gearbox
- Air filter, air hoses, pipes, charge air cooler, exhaust system, etc.
:thumbup:)
Oddly, the code 4530 doesn't seem to come up under the DDE 4.x but it is mentioned in the DDE 5.0 (which I have on my LCI): -
https://www.newtis.info/tisv2/a/en/e...tuator/XcGISOp
Time for a big reading session, my friend! Good luck!! ;)
