hi, i have 1.8T agu engine, chipped to 195bhp, and it lost all its boost.
checked no boost leaks, no vac leaks, try to put new n75j and DV 710N but nothing, changed g62 coolant sensor and spark plugs, changed line from inlet manifold to PCV valve, all vac lines changed an tied with metal ties, maf reading normal around 2,9g/s idle, around 142g/s at max, no ecu errors over vagcom, lambda is +15% at group 06 MULT field(second field) seems normal, changed vac line from brake system to inlet manifold, cleaned IAT and MAF, even try to disconnect all sensors, and even disconnect from battery. checked PCV system, PCV valve is fine blocking in one direction. fuel consumptoin is fine with or without boost.
I have no boost at all, i cannot hear it any revs in any gear. Sometimes i have all its power and running for few days, and suddenly its just loss at its power and sometimes when i start car in the morning i have half of my power. same problem is when temp. is 25C or -5C.
So when car sometimes running great, turbo is sucking air you can hear it, its very strong suck of air, and pull is amazing.
help please