What should my pressure be? Make Model Spec ASTRA H. 1.2, 1.4, 1.3 CDTI, 1.6, EDITIONASTRA H. 1.4, 1.6, 1.3 CDTI, 16 OPTASTRA H. 1.4, 1.6, 1.3 CDTI, 16 OPT IIASTRA H. EDITION, SPORT, COSMO 17 OPTASTRA H. EDITION, SPORT, COSMO 18 OPTASTRA H. SPORT, COSMO MODELS