95 240sx auto to manual conversion super high idle 2600 rpm

[garageworx]

I just bought a 95 s14 the previous owner did a auto to manual swap on it but it didn't rev. past 2000 rpm. I swapped out the mass air flow sensor and it revs. up to 6400 rpm but it idles at 2600 rpm and the temp needle shoots up way past the h. It even moves up with the ignition on before the car has even ran.