I called a chevy dealer today and they wanted $85 to pull a code!

I went then to autozone and the guy did it free for me. It pulled code P0142 (or 1042?) and said "System too lean (Bank 2).

Any ideas what this most likely is? The car is acting like normal, running just fine.. I did a search and didn't come up with much info except maybe bad O2 sensor? The car is a 96 and just turned 80k miles.

Thanks for any and all help

Jeff

 

time to change your o2s i did

 

ok, thanks, will do.. One more question - will I do any harm driving it still?

 

One more question if someone can help me out: I pulled the fuse to the PCM for 20 mins or so, and reset the code. The SES light never came back on. Is it safe to assume it was a fluke and I'm ok? When it went on originally, it was idling for about 10 mins. Could that have caused it to come on?

Thanks

 

if it's not your o2 then one of your wires/plugs isn't firing. You'll have to pull the plugs to find hte black one. Replace that wire and/or plug.

 

I think thats jumping to the worst conclusion a little early. O2's are definitely causing the code. Resetting the PCM will supress it for awhile, but as soon as the PCM relearns the fuel tables, it will pop up again, most likely on a deceleration or coming to a stop. Be prepared though O2's are about $50 a pop for the cheap Bosch Autozone ones and are about $80 from Jason Chromer. Don't go to your dealership or you will be spending upwards of $100 on each.... So find out which one it is exactly or spend the $200+ and replace them all....

 

Ok, great, thanks for the tip.. Any easy way to find out which is the culprit without a logger or a diagnostic tool?

Thanks

 

Unfortunately I am not entirely positive for your vehicle. Different computers. But someone will know....

 

Well I had the same problem. I didn't think it would be a misfiring/dead wire, but that's what it turned out to be.

I had a loss of power, the powertrain would vibrate/shudder horribly in overdrive gears (6th very bad, 5th somewhat noticeable), and on my scanning utility software it said that one engine bank was running very rich and the other was running very lean.

I swapped the injectors from one side to the other, same problem. I checked this and that and the other thing, same problem. Finally I started pulling plugs and I found one to be very foul, and the wire to be a little crisp. So, I changed 'em out and voila, it works great.

 

When you only get the "lean" code on one bank, its usually:

-exhaust leak on that side before the O2 sensor
-misfires on that side
-bad O2 sensor on that side.

The code sets because the long term fuel correction has max'd out at 160 and hasn't cured what the PCM "perceives" as a lean condition. If its an exhaust leak or misfire, replacing the O2 sensor won't help you.

And, it might not just be limited to the one bank. The other bank might be approaching the point where it will set the "lean" code... just didn't reach it yet.

A "scan" will help, because that allows you to look at the long term fuel corrections, under what load/rpm conditions the problem occurs, the misfire history, and the actual O2 sensor readings.

"Resetting" may have cleared it temporarily, as indicated in the above, and it may reappear once the long term corrections have fully developed. By the way... pulling the fuse 30-seconds is all it takes to clear volatile memory.