[bonneville Joe]

I know this indicates a lean o2 sensor but what to do to fix it? The O2 sensor is a newer bosch unit I installed about a year ago. Is it the sensor or what do I have to do to fix the problem in the engine itself?

[WW3]

Well being an 88 GTA I assume it's a TPI engine and therefore it will be a MAF type airflow management system because post '89 and up to 92 used a MAP or speed density. Basically(MAF) that means all air entering the engine is measured through the MAF sensor at the end of the rubber boot (intake side) at the throttle body.

A 44 code means the ECM percieves a lean mixture or low voltage produced by the O2 sensor (less than .2 for a period of time). There could be a handfull of things to check and the first would be the O2 sensor, but that's been changed and we'll assume it's okay for now.Next I'd check to see if that purple wire to it has burnt on the exhaust manifold or is shorted to ground somewhere close by. Next I'd be looking for a vacuum leak or any place air could be intruduced into the plenum. That is called "false air" because the MAF hasn't measured it coming into the engine and it's dilluting the air fuel ratio making it lean. Next I'd get a fuel pressure gauge and measure fuel pressure at the rail. I think it should be around 30 PSI running, maybe a little higher by 10-15%. Low fuel pressure could be causing the injectors to be not putting enough fuel in per duty cycle that ECM commands, but the ECM doesn't know it has low fuel pressure.

There is also a possibility that it's just another bad O2 sensor as these things are sensitive to fuel additives and silicons.

What you really need is data stream scan tool so you can see if the O2 sensor is functioning(producing a changing voltage) and how much gps of air is moving through the MAF sensor at idle and part throttle.

[bonneville Joe]

I messed with it all afternoon and figured out it had a bunch of cracked vacuum lines. Im gonna take it out later and see if that did the trick.

[WW3]

That would do it...false air