Hi

Customer complaining of power loss @ 80mph after 20/25 miles, have 2 codes coming up P0672 & P0234, the first, P0672, glow plug circuit cyl 2, we have ignored as we don't think this is causing the problem. But P0234 is telling us that we are overboosting(intermittently),we have checked vacuum pipes,all seem ok, cleaned out variable vanes with cleaner.We cleared the codes & road tested after about 20 miles, loss of power, same two codes, serviced engine, road tested, ok!!! Left overnight, road tested and again after 20/25 miles, loss of power & the same codes,we fitted a solenoid block(waste gate control valve unit)thinking it might be the fault but still losing power, lots of info on websites but no FIX!! Has anyone out there come across this fault.
Hope the above makes sense!!
thank you John