I’ve been battling with setting my TV cable after a trans install in my 91 Firebird, and now that it’s set, I’ve come into a new problem. It started when trying to set the cable, originally I was opening the throttle by hand. Now it starts right up, actually faster than ever, but the idle drops down low and it runs really rough for a few seconds, then it clears up and runs great... except for the fact that I seem to be using a TON of fuel. I’m stumped because there’s no black smoke except for at startup, and with the amount of gas it’s burning through I’d expect the exhaust to make your eyes water but it really doesn’t seem any different from before. It doesn’t matter if it sits for 10 seconds or overnight, it behaves the same way. Does this sound familiar to anyone? I’m completely stumped.

 

1. Connect a scan tool, start looking at short- and long-term fuel trim numbers, coolant temperature, knock sensor data for the fuel consumption problem. I'd be looking at the IAC and TPS for the idle speed problem. The data stream is probably more helpful than any stored codes...but codes are not to be dismissed.

2. Overly rich mixture produces high CO emissions. CO is colorless and odorless. No eye-burning. Eye-burning exhaust is typically misfire, which blows HC emissions out the tailpipe. HC makes your eyes burn. And all of that largely goes away when pushed through a catalytic converter. (But it's not good for the cat.)

3. What is the fuel pressure?

 

(sticks eyes into exhaust stream to test for HC)


Am I doing it right? *red eyes*



Oh wait, theres no cat... *passes out*

 

Not so far from the truth. Funny, though.