That P1128 code would lead me to believe that there is a vacuum leak.

What is the mileage?
The 02 sensor will get sluggish as it gets older. It could possibly solve
your problems.

Are you using a tool like the ross-tech.com scanner? AFAIK It will allow
you to see what the 02 sensors are doing. It should also give you a little
more info on those codes too! ;-)
I would want to check the Coolant Temperature that the ECM sees though.
--
later,
dave
(One out of many daves)

> wrote in message
ups.com...
> Looking for opinions, I have an issue where the check engine light is
> coming on. I recently gave the car a tuneup which cleared the misfire
> codes it had, but now (1 week later), I have the following codes
> present:
>
> P1128 Long Term fuel trim too lean
> P0172 System Too Rich
> P0134 Oxygen Sensor Circuit - no activity detected (pre-converter
> sensor)
>
> I am guessing that the O2 sensor needs to be replaced, but will this
> also fix the other codes? I haven't detected any vacuum leaks that
> might be suspect. Any help would be appreciated. Thanks.
>