i've vagcom my car and engine shows no error codes. i suspect that fluttering noise could be due to insufficient fueling from my autotech pump as i'm running an APR k04 software. but if there's not enough fuel pressure, engine error should appear in vagcom right? i've tried replacing the carbonio intake back to stock intake and the boost still not holding steadily and have fluttering sound. i've still no idea wat the problem is. will check DV & next is to try an APR fuel pump.
Have you had the official VW recall for the faulty fuel pressure sender? If not, and it is faulty, then vag-com may be incorrectly reporting, hence why you are scratching your balls and getting nowhere!
I seriously doubt it will be the fuel pump, because earlier in the thread, you indicated it made very good top-end power. Any weakness in fuel delivery will be obvious at top-end too.
If the boost really is fluctuating, then check the tightness of all the intercooler and air intake hoses and seals. Is the intercooler itself in good nick, without any internal or external damage. What about your MAF - have you ever run a non-standard or oiled air filter, or no filter at all?
And finally, even though you have the latest spec OEM recirc valve, the diaphragm could still be torn.
HTH, but please get the recall checked out.
If you like, PM me your VIN, and I can check online for any outstanding workshop actions.
