[bmwdiesel]

hello, so basically here is the deal. I changed glow plugs and egr solenoid and car gained the lost low rev power, however it still wasn't 100%. But after I changed oil, the car lost even more power and my explanation is this: engine capacity is 7.5l for 335d 2007. mechanic put 8.4 quarts while checking the dip stick, but to add he didn't let out all the oil and I suspect there was left another 0.5 quarts.
so is it possible that increased pressure form 1 quart plus oil in engine would find its way out and leaving some small hole along where the Intake is losing the manifold pressure?

INPA live read outs show that even when idling the actual Charge Air pressure is about about 800, while desired Charge Air shows about 1000.
when I press the accelerator while idle, Actual either doesn't climb, or after some delay it climbs a bit, but it is not reaching the desired values, or only with big delay when I accelerate some more....

I mentioned the oil change for reference, even tho it can be placebo, but I felt I lost some 20-30% torque just after when I left the garage tbh.

so what could be other causes of low charge air pressure ?
it doesn't throw a code to speak of, only live data it shows it is not reaching desired levels, if that makes sense. thanks

[dmanb2b]

Check red boost (at turbo) hose for leaks or possibly valve cover gasket

[bmwdiesel]

thanks, yes red boost is little oily and dusty, but as is almost the whole compartment underneath an engine and some other parts. valve cover gasket was already mentioned and I even have that gasket, but it seems like hell of a huge job, considering all torque momentum and cross tightening, that scares me off big deal....so i guess it won't be a cheap fix. and just to add, yes i lean towards the second option