Check engine is on , I've got five codes comming up: P0442 (small leak in my EVAP); P1177 (O2 Correction Behind Catalyst,B2 Limit Attained); P1136 (Long Term Fuel Trim Add.Fuel,Bank1 System too Lean); P1138 (Long Term Fuel Trim Add.Fuel,Bank2 System too Lean); and P0703 (Brake Switch "B" Circuit). Wow, I got rid of four codes and now I have five come up. The P0703 code I'm assuming there is a bad connection between the brake switch, I'll look at it this weekend along with the small EVAP leak. What I am concerned about is the P1177; from what I've gatered the P1177 could mean I have a bad catalyst, but which one? driver's or passenger? I am hoping the the P1138 and P1136 codes are comming from a hose leak. Does anyone have any experience with these codes?

 

First, address the vacuum leak you apparently have....that is likely what is causing lean burning conditions. THEN I would see if the cat code still persists...may be caused by the lean burning conditions.
P1117 is a code for the 02 sensor AFTER bank 1 (pass side) cat...could mean cat problem, that O2 sensor problem or even the upstream sensor, sense the 2nd sensor's (one the code is for) job is to double check the 1st sensor AND the cat performance...I'd leave that be until you correct the lean problem.
Did you tighten down the loose O2 sensor you mentioned in the other thread?

 

I did tighten the upstream oxygen sensor on the driver's side in hopes that would take care of the problem, it didn't. I'll check my hoses this weekend to see if any have gone bad and need replacement, I found these websites that recommend the replacement of these hoses; are these the hoses I should focus on?

http://www.audipages.com/Tech_Articl...atherhose.html
and
http://www.audipages.com/Tech_Articl...sereplace.html

 

Yes, all those should be inspected carefully for any place that can suck in air, which gets to the intake unmetered and leans the fuel mixture. Don't necessarily need to replace everything involved, unless it's noticeably worn/degraded.
Plus check all plastic intake tube and rubber boot connections going to throttle valve.
Also worth actually grabbing large vacuum hoses with engine idling, to see if you hear/feel sucking air when you move/bend them. A pro (or someone with access) might even use a smoke machine (or equivalent) around the engine to look for smoke/mist drawn in.

 

Sounds like a plan, it'll be on my to do list. I really hope this is the case, I don't want to fork out that kind of money for a catalytic converter or sensors

 

So I checked my intake hoses, found a hole in one of the rubber elbows but other than the all of the other hoses loocked like they were in good condition. I'm going to try to clear the codes and see which ones come back. There is a very strong exhaust smell, I am worried that the catalytic converter has in fact gone out, it doesn't make noise though.

 

I replaced the brake switch and cleaned my MAF after fixing the holes in the intake tube, cleared the codes, only two to came back. P0422 and P1177. Is there a way to check if my oxygen sensors work before I try to replace them? Has anyone had experience with aftermarker oxygen sensors and catalytic converters? The dealer is asking for $100 for each oxygen sensor and $700 for the catalytic converter aftermarket is less than half of this.

 

I cleared the codes, the P0422, P1177, and P0703. I've replaced the brake switch but the code keeps coming up. Looks like I'll have to replace my catalytic converter, the car has a really strong smell of exhaust and there's a slight rattle when I accelerate coming from the passenger side.

 

I've replaced my front sensors with Bosch universals (# 15733) about $50 each from PartsGeek (cheaper from places I haven't done business with)...not terribly difficult....exactly the same as OEM Bosch's...you just have to connect to original plug harness. also not difficult.

A link to my change procedure:

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