intermittant power loss 3.0dci grandespace 2004

hiya forum



im the owner of a 2004 3.0dci grand espace initiale, on the the whole it has been a real trooper, never suffered from the usual gripes you hear or read about,however, in the last month it has suffered from a strange loss of power under load very akin to a "miss" accompanied by black smoke,but can run fantastic the very next day,am at a loss as to the cause, it is with a very competent garage at the moment who are also stumped, I will list the action that has been taken



.engine ECU removed & tested,no fault found

.turbo & all hoses checked

.full service inc gearbox oil changed

.full diagnostic check undertaken,no fault codes held

.no warning lights have been triggered on dash

. EGR valve removed & blocked off.



any pointers will be appreciated

many thanks