Hey Guys, Im back in business as of today cuz I just bought an 89 Formula 350. The car is all stock except for a Flowmaster catback, a custom Y Pipe, and the Cat was removed. The car runs o.k. but seems just a lil sluggish off the line. It's also throwin a check engine light(which I will get scanned soon) but what I was wondering about was the loud hissing noise at idle. Its seems to be coming from under the car and it goes away while on the gas. Could this be something with the air injection system? Cuz from what I remember it should plug somewhere into the cat.(which has been removed)

 

Could very well be the AIR system. Is the rest of it hooked up? The AIR feeds exhaust from your headers down to your cat, and if that cat is gone and the AIR is still there, then all that air is just getting let out of the pipe that was hooked up to the cat.

 

thats what i was thinking. im gonna check it out tomorrow and see if the air pump is even still on the belt drive.

 

might explain that code too,

 

from what i understand the smog is not controlled by the computer. i have removed my smog pump and left the end connectors unplugged and it hasnt thrown a code.

 

yes same with me. I did my 87 and my friends 89 trans am. No smog pump, no code. My 1st bet on the code is the O2.