Codes 176 AND 177?

[Chythar]

I have a decent idea as to what's causing the codes, but I wanted to run it by you guys. Bit of background: I have to get my GT smogged by next week in order to get my registration done here in Los Angeles. Not a big deal, except I have a Bassani x-pipe with hollowed-out cats on the car. No cats, no pass. I'm more than willing to be legal, so I bought a pair of Bassani's new cats (25MSC) to put on the pipe. These cats are a new honeycomb-design on the inside, which should have less restriction of the exhaust while being just as efficient (I hope) as the OEM cats. Me and a friend have been busy the past two weekends installing them. We had to fab up some brackets to get the cats on the pipe, hoping we could just clamp it all together. It seemed to go well, no problems on a test drive yesterday or driving to work and such today. On the way home, the check engine light flashed on, then went out a few seconds later. Back on, then off again. It did this until I got off the freeway, then hasn't come on since.

I checked codes, and got:

176 - O2 lean on bank 2
177 - O2 rich on bank 2
212 - SPOUT circuit grounded
334 - EGR closed valve voltage higher than expected

I didn't expect to get 176 AND 177. This is bank 2, the driver's side - correct? If so, it does make some sense. The driver's side cat was really close to the unibody, and I could hear a thump under my legs periodically during the day.

First (and only) thought is that the pipe has come loose and is letting outside air in as the car bounces around. This might explain both the 176 and 177. No way to really know until I get under the car.

I don't see how the 212 and 334 codes are related to this issue - they could have been in memory for a while without throwing a CEL. Any thoughts?

 

[skeptiq]

I was getting the CEL flashing for a bit. I cleaned the mass air sensor and the CEL hasn't come on since. The mass air sensor was filthy. Bought a can of cleaner at autozone and all was taken care of in a matter of minutes. Not sure I was getting the same codes as autozone wouldn't read the codes since the CEL was always off when I pulled in to get them checked. Worth the $5.00 can of cleaner to see if that fixes the issue though.

Good luck,
Ben

 

[Chythar]

OK, a bit more news. I cleared codes and went in to work. No problems until I hit the freeway, then the CEL came on again. It did turn off and on a couple times, but stayed on when I exited the freeway and pulled in to work. The codes are now as follows:

KOEO:
542 - Fuel pump secondary circuit failure: PCM to ground

Memory Codes:
176 - O2 lean on bank 2
212 - SPOUT circuit grounded
334 - EGR closed valve voltage higher than expected

I've cleared the codes, and I'll check them again when I get home. If code 334 is still there tonight, looks like I need a new EGR. What about code 542? Would the intermittent 542 be cause by a short, or a bad ground? Also not sure what to do about the 212 code. The SPOUT is in and seems to visually be OK.

 

[Chythar]

Forgot to update last night. Still got the same codes, so 177 seems to have been a ghost or an old code. I cleared codes then ran KOEO again to make sure they were gone. The 542 code is still there. I popped under the car this morning to make sure that the left O2 was plugged in all the way, and it was. I re-seated it just in case. We'll see what happens on the way to work today.

Even with a fuel pump code, I'm getting fuel with no apparent problems. No stuttering, no problems starting, nothing I've noticed. Very unusual.

 

[Chythar]

WOW! Major SOTP improvement! Ran like the proverbial raped ape on the freeway today. I thought I felt a power loss along with the CEL, but I've been driving the Cobra the past week; thought the power loss was just the difference between the Cobra and the GT. Apparently not! No CEL so far, but I can't check it until later (left the code reader at home). The SOTP boost has me feeling very hopeful now.

 

[Chythar]

No one with any feedback? I thought someone would pitch in an idea or two. I believe the issue is now resolved. The 176 code is now gone, no CEL, KOEO comes back with 111. Code 212, 334 and 542 are still there for memory codes, I'll have to check them again tomorrow to see if at least 542 is gone.

Any thoughts into code 212?

 

[toyman]

How are you removing the stored codes? If you are disconnecting the battery you are also losing the KAM that has stored all the learned settings. The proper way is to remove the the jumper wire from the diagnostic test connector when the codes start to display. The other thing to remember about CEL's is they are predominately sensor failures that affect emission controls.

Were you saying that the SOTP's improvement was connected to the O2 sensor when you reseated it? Quite possible and as the O2 sensor is an emission related sensor it will trigger the CEL.

 

[Chythar]

I am removing the codes via an option in my Actron scanner. I select it, it re-starts the KOEO and says it has cleared the codes. And yes, I was saying that re-seating the O2 sensor connector improved the SOTP power. It also eliminated the code 542 and the memory code 176.