L98 starts right up for about 20 seconds then dies,gives codes 44 oxy sensor lean,and my gas mileage has been noticably bad has of lately....sound familiar to anyone???? 89 gta 72,000 miles excellent shape,usually never gives me a problem

 

O2 sensor shouldn't keep it from running. Also shouldn't even being looking at it until the engine warms up a bit.

What have you verified when it dies? Have spark? Have fuel pressure?

 

It had rougly a 1/4 tank of gas in it,and had been sittin for a few weeks,i noticed a lot of water in the exhaust,so I put some'iso heat' in the tank,it started and ran just fine after that,therfore a possbility of bad or water logged gasoline. The code 44(oxy sensor lean) is from the last time i drove it, Im guessing"from what Ive read on this site using the search engine that...my fuel pump is about to go out,and is currently not suppling enough fuel therefore making my o2 sensor read lean,and stalling out when trying to run the car with less the a 1/4 tank of fuel.. hail to the 3rd gen search engine

















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