Engine Mechanical problem
2005 Vauxhall Astra 4 cyl Front Wheel Drive 89000 miles

please could you help i have been having trouble with fault code p0170 on my astra h z16xep the car seems to drive ok iv replaced front 02 sensor egr valve and still it appears the map is reading 32 at idle and maf is reading 1.9 kg/h all i can think of now is its a maf sensor fault or air leak any help would be great thanks