2003 Sable bank 2 lean condition

[treebound]

Hi,
First post here, plus currently browsing with a cell phone so I'm search function limited (and typo prone with the mini-keyboard ;-) ), I'll check the site better later with the home computer.

Wife's car, 2003 Merc Sable, V6 engine, just over 100k miles. Running rough and almost stalling at idle, seems fine at higher revs.

Got a scan at Autozone yesterday which indicated a lean condition on bank 2 and pointed to the bank 2 sensor 1 oxygen sensor. So bought one of those, then went back and bought the slotted socket, and replaced the front sensor. Didn't fix the issue. My wife took my car to work (she doesn't like my manual trans) and I took her car to a different Autozone at lunch today and got another scan. Today's guy said it probably wasn't the sensor and to try a bottle of some injector cleaner. Dumped that in the gas tank and filled it up the rest of the way.

The error code printout reads:
- - - - -
00 Fuel trim bank two condition
Explanation
00 The ECM has detected a rich or lean air/fuel ratio condition on engine bank two
Probable cause
001 If bank one and two are set together suspect a fuel pressure condition or MAF sensor fault
002 Failed H02S21
003 Ignition misfire condition
004 Fuel injector problem
005 Engine mechanical condition
- - - - -

Hopefully it isn't the last one. I did some google searches earlier and answers ranged from looking for shorted wires, vacuum hose leaks, intake manifold gasket leaks, various sensor and valve replacements, and assorted other resolutions.

Since I've already replaced the bank two sensor one, what should be my next option while I let the magic juice injector cleaner do it's thing?

Thank you for any suggestions and I will follow up with what I find. Hopefully it will be an economical fix since my day job recently cut my hours, otherwise I'd be tempted to just take it to the dealership. I don't like chasing down computer gremlins.

[treebound]

Update and further info:

Last Fall we replaced the two EGR lines where the boots/lines were disintegrating or decomposing. Car ran fine all winter.

Last night I looked around under the hood and didn't find any obvious wiring shorts or leaking vacuum lines. I put in a new air filter and disconnected the battery for a few minutes before reconnecting it.

The check engine light went out but the symptoms persisted. Then this morning on the way to work the check engine light came back on.

We've got an almost indirect relative with access to an OBDII code reader so I'll see if I can get any codes out of the car with that over the next couple of days.

Car problems are no fun.

[shorod]

Having the exact code number will help. Also knowing which V6 engine (24V Duratech, 12V Vulcan) would help as well. When you have the exact code and get back to your home PC, try searching this forum (as well as the Taurus forum) for the code. The code should be in the form P0123 but you might also try Po123 as some people use an 'o' instead of 'zero.' There are some lean condition codes that are caused commonly by the PCV lines on the Duratech if I recall correctly. Someone post a bit of a 'how to' on the Taurus forum for this.

-Rod

[treebound]

It has the 24valve Duratech engine.

Last night I had my wife keep it running while I did a spray test and couldn't find any vacuum leaks around the intake manifolds. I also checked for voltage at the IAC valve connector per instructions in the hayes repair book I have and I got voltage there.

I'm running down to see a friend after work today with afterhours access to their shop scanner. Hopefully I'll be able to get the actual codes and maybe even be able to ping individual components.
I'll follow up with what I find.

Thanks.

[treebound]

Got it scanned last night and while looking it over we found a hole in a rubber PCV line elbow. Real hard to see without good lighting.

Replacing the PCV line tomorrow along with doing some component cleaning per my service manual.

Here are the error codes that his Snap-On scan tool gave:

P1504
P0136
P0156
P1131
P1151
P0171
P0174

This could have got real expensive if I'd have just taken the car in to a questionable shop or to one where a tech just throws parts at it. Stepping up my plans to buy a scan tool.
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