My 2000 yukon denali sometimes will Start up Fine and dont start at all . It can on 2000 GMC Yukon Denali

Start issues also ruff idoling at a light had fuel pump check got good pressure fuel guage sapiens around when starting oil pressure guage reads Fine when drops after driving 20 miles when I Drive not good power on take off go yo a Store cut offmy suv come back and I have to give gas to start it when it does start it is sluggish...

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