Hello, i have an 04 Vectra with EGR issues. In May it had the sensor replaced as it was lean surging. Problem seemed to be cured but recently its been recording a low flow error. Local dealer updated the EGR software and replaced the thermostat & said all fixed but not the case and in fact became worse with the engine mgmt light coming on constantly and the emission control warning light permanently on.
Now escalated to service manager and their senior tech. They have done further update including (they say) an EGR software update not publicly available that they got from the factory in Luton. Today got a call saying they've removed 2 pipes from the inlet manifold. They dont know what the pipes do or why they are attached (!) but state has cured the lean surging. Does anyone know what these pipes may be and what they do.
Many thanks, Medway