1996 Ranger 5.0L help

[josh-the-ranger]

I have a 1996 ranger 2wd with a 5.0 swapped in. Recently it started running rough at idle. It will idle rough fluctuating between 300-600rpm and die after 30seconds-1min if not given gas. It almost feels as if its got a miss at low rpm's but I think this is due to the rough idle. Also if I am going highway speed and give it more than half throttle going up hills and so forth the a/c will cut off and go to defrost as if it looses all vacuum, my vacuum/boost gauge shows it has no vacuum when I give it full throttle. I have a supercharger but it is off currently because it needs to be rebuilt. I have changed the plugs but to no avail. I have also looked for any vacuum leaks. Could it be the tps or fuel filter?

 

[josh-the-ranger]

It is a fuel injected 93 cobra block with twisted wedge heads, headers, cobra intake, magnaflow exhaust and has a fmu

 

[Teddyzee]

For the heating, there should be a check valve before the vacuum ball/can to prevent this.

For idle, search "base idle reset" on sbftech.com It's simple, but works. I code 67 will also cause a rough idle- that's caused be the neutral switch either from the trans or the clutch pedal (not the starter interrupt). Mine is hardwired as my Ranger had no trans switch to begin with.