Running Lean
 

I've recently upgraded my 95 GT with some intake and exhaust parts only now the check engine light comes on. The upgrades include MAC cold air induction, 65mm throttle body, adj. fuel regulator (42psi), 1 5/8" unequal headers, Prochamber h-pipe, Borla catback exhaust, new O2 sensors, PCV valve and a digital air/fuel gauge. The error codes say lean mixture left and right banks and a grounded SPOUT circuit. The air/fuel is .14 at steady throttle, .98 as soon as let off gas, then down to .03 after coasting a bit. I don't see any vacuum lines off. Am I missing something simple? Has anyone had an experience like this?

well i would replace that spout, definately check all sensors, you said you replaced the 02's but try resetting the computer and see if you can get rid of the check engin lgt.
how does it idle?

I've have cleared the codes once before and it idles fine and sometimes it feels like it runs strong and other times it doesn't. Do you know what is involved in replacing the SPOUT? I'm not sure where to look except that the SPOUT connector is under the MAF and that it's pulled when you adjust the base timing without any changes from the computer. I have a couple more O2 sensors to try out. I also tried the TPS and it read .96 volts.

Well the spout is bye the distributor on my car, probaly different on sn's, that little plug, replace that, i mean if your getting a "spout" code, it shouldnt be much $ to replace, also check the wiring, make sure everything is plugged in, injector plugs ect...

I reinstalled my K&N FIPK and the engine light has not came back on and the A/F gauge reads as it should. The bend in the CAI before the MAF sensor must have been the culprit.