Hi, I have 90 ls 400 and at this point iam lost , iam getting a code 24 its rattleing like it has bad gas and has no power if i get into it it ethier dosent go at all or it goes a litle over 4 grand and dosent have any power , i have changed fuel pumps drop my muffers and pipes fuel filter and M.A.F still the same.iam thinking maybe t.p.s any ideas ???