just replaced my series 2 ptu with a new series 2 ptu now my engine won't start, turns over but no start, any ideas? new subharness as well, 91 5spd na

 

Make sure the grounds are connected. One on plenum at rear on passengers side. One behind coil pack 6 one on frame above ac compressor, if they are not good the ptu will not work and you may try the ptu. Take them off clean where all contacts are made with wire brush, sandpaper or the like.