Need help with 1990 f150 302 efi

[21SF]

take out the oxygen sensor and take it down the road
if it improves you know what the problem is

No emissions

 

[41mag]

Check for vac leak , especially around manifold edges and plenum.

Also i would check the TPS with an analogue meter. Check for slow steady sweep to see if needle jumps sporadically.

Hard to diagnose when you cant put the hands on it

 

[8675309]

No emissions

stopped up muffler can do the same thing