hard to start and bogs down

i have a 1991 toyota camry with a 2.0 liter ,150,000 milles it is very hard to start when it does it idles great but when you gas it it bogs down i have checked spark it is strong, i have checked fuel pressure it is 40psi at idle spects states it needs 37psi too run correct,i also have good air flow no blockage in the exhaust,i tested the TPS sensor and the MAF sensor basicly everything that makes a engine run like a champ is working! but it is not what am i missing its driving me crazy