1998 Buick Park Avenue code p0171

1998 BUICK PARK AVENUE
170,000 MILES • 3.8L • 6 CYL • FWD • AUTOMATIC
Avatar
LOSTASUSUAL
  • MEMBER
  • 1 POST
need to pass smog check , code p0171 keeps coming up , no vaccuum leaks , fuel trim on bank 1 sensor 2 is up to 99% bank 1 sensor 1 is 25 % at idle , system showing open loop only , upstream 02 sensor showing about .25 volt , downstream at .98 ,.......tps showing +4 at idle ............ .I changed a injector on cyl 7 a while back that I got at a wrecking yard
,...is it possible from these numbers that the injector I got is either the wrong one or bad? ....I've checked about every sensor I can find a test for and haven't found anything out of range ,....never checked downstream 02 ......any help to narrow this down or pinpoint would be appreciated ....thx
Dec 10, 2015 at 10:59 PM
Advertisement
Avatar
CAR-MAN145
  • CERTIFIED EXPERT
  • 321 POSTS
Your upstream o2 sensor is lean at .25 so I would see if you can make it go rich by spraying carb cleaner in the air intake o2 sensors are made to fail lean. So if the upstream is lean the pcm if trying to richen it up so is dumping fuel and that is way you down stream o2 is rich so I would not think you have a bad injector
Dec 11, 2015 at 1:32 AM