CEL code 1126, 1133 and 0154

[Swhitcomb]

Tried posting in tech forum but no help.

Hi guys. Just joined. Bought myself a 2.7 Boxster Base on Friday for my 37th Birthday. Took it about 30 miles to go to dinner with my wife. On the way home, 5 miles or so into the ride, or about 70 after I bought it, the CEL kicked on. Took it to Autozone today. Codes read as follows:

P1126
P1133
P0154

Thought perhaps an injector was dirty. Filled the tank, put in some injector cleaner, and drove it about 3 miles. It's missing quite badly now. I'm at a loss where to start. I have done a search and found dozens of things for all those codes. I'm hoping someone has enough experience to see all three and see a reason all three are connected.


Another issue I'm having is with the key. The door lock button had broken off inside the FOB. Using the search here, I fixed it. The LED now lights and the switch is fixed. However, it won't unlock the car or either trunk.


I really like this car and am looking forward to years of ownership. HELP!

[Chuck W.]

OK.... This is just a guess on my prior experience. It may be as simple as the MAF - Mass Air Flow Sensor. When mine went out it throw several codes too. One of them was P1126. Cleaning it didn't work and after some searching I figured it was best to buy a Bosch for $170 from RockAuto. The OEM ones from the Porsche dealer are very expensive. It was an immediate fix.

I hope this is it as it is an easy fix. Good luck and keep us posted.

[gavinyuill]

P1126 Oxygen Sensing Adaptation, Lower Load Range, Bank 1 - Below Limit
P1133 Oxygen Sensing Adaptation, Lower Load Range, Bank 2 - Below Limit

No idea what P1054 is.

Probably a MAF problem, but could also be:

– Intake air system leaking
– Fuel pressure too low
– Volume supply of fuel pump too low
– Fuel injectors fouled
– Exhaust system leaking

[Swhitcomb]

Originally Posted by gavinyuill

P1126 Oxygen Sensing Adaptation, Lower Load Range, Bank 1 - Below Limit
P1133 Oxygen Sensing Adaptation, Lower Load Range, Bank 2 - Below Limit

No idea what P1054 is.

Probably a MAF problem, but could also be:

– Intake air system leaking
– Fuel pressure too low
– Volume supply of fuel pump too low
– Fuel injectors fouled
– Exhaust system leaking

Thanks. Think I typed wrong. Think may be P0154. I'm at work and it's at home so I can't check it.

What would my best course of diagnostic action be from here?

[Swhitcomb]

Originally Posted by Chuck W.

OK.... This is just a guess on my prior experience. It may be as simple as the MAF - Mass Air Flow Sensor. When mine went out it throw several codes too. One of them was P1126. Cleaning it didn't work and after some searching I figured it was best to buy a Bosch for $170 from RockAuto. The OEM ones from the Porsche dealer are very expensive. It was an immediate fix.

I hope this is it as it is an easy fix. Good luck and keep us posted.

Hadn't thought of Rockauto. Thanks!

[Jager]

Try disconnecting the MAF Sensor and see how the motor runs. Do this just long enough to test, don't drive too far without the MAF Sensor connected.

[hancock1701]

I have had those two codes P1126 and P1133 for a few months now. They would come on every 100 miles after I reset them. Tried to clean the MAF twice. My plan is to test the intake for leaks before I go with a new MAF. However, the car has been running fine with the two codes on.

[Swhitcomb]

I checked it last night. It's P0154. Not sure how that fits in with P1126 and P1133.

[paulv]

Originally Posted by Swhitcomb

I checked it last night. It's P0154. Not sure how that fits in with P1126 and P1133.

Since P0154 is an "Interruption of Signal" on the upstream O2 sensor (Bank 2) this could be a wiring problem (signal or ground) or the O2 sensor itself. Sounds like this problem could also cause the P1126/33.

Regards,
paul...

[particlewave]

Yep ^

That 0154 is usually a bad connection at the connector. Pull it off, clean the connectors, and re-spring the contacts a bit for a snug fit. After that, clear the codes and see if they come back.

[Swhitcomb]

Thank you very much. I sent the dealer I bought the car from an email that I wasn't satisfied with my experience. Didn't expect any answer. They called within 5 minutes and offered to fix it. We'll see how well that goes. I was going to fix it myself, but if they're going to offer, I'll take them up on it. If they don't get it right I'll post on their Yelp.

[Topless]

Originally Posted by Swhitcomb

Thank you very much. I sent the dealer I bought the car from an email that I wasn't satisfied with my experience. Didn't expect any answer. They called within 5 minutes and offered to fix it. We'll see how well that goes. I was going to fix it myself, but if they're going to offer, I'll take them up on it. If they don't get it right I'll post on their Yelp.

It sounds like a simple fix. If they make good on their offer be sure to post that on yelp as well.

[Swhitcomb]

Originally Posted by Topless

It sounds like a simple fix. If they make good on their offer be sure to post that on yelp as well.

I will. I find it hard to take Yelp seriously when you find people that only post negative. I post positive experiences too, and allow the company time to change my opinion before I just post a negative review.

Generally though, I have a very negative view of modern mechanics. They've stopped being mechanics, and become parts replacers. If it gives an O2 sensor code, they just replace it. They don't follow the diagnostic tree on WHY it threw on O2 code. I've seen it time and time again with friends and family member's cars. Within a few 100 miles the CEL comes back on, and they're out the price of an O2 sensor and labor, while the original problem still exists. OBD II is a great system, but very missused. People go to Autozone, get the code read, they replace that part. That's not how OBD II is supposed to work. It's why I do all my own work. I don't hold out too much hope they will get it right, especially because it's a Subaru/Kia dealer, but I could be wrong and very happy.

[Topless]

Originally Posted by Swhitcomb

I will. I find it hard to take Yelp seriously when you find people that only post negative. I post positive experiences too, and allow the company time to change my opinion before I just post a negative review.

Generally though, I have a very negative view of modern mechanics. They've stopped being mechanics, and become parts replacers. If it gives an O2 sensor code, they just replace it. They don't follow the diagnostic tree on WHY it threw on O2 code. I've seen it time and time again with friends and family member's cars. Within a few 100 miles the CEL comes back on, and they're out the price of an O2 sensor and labor, while the original problem still exists. OBD II is a great system, but very missused. People go to Autozone, get the code read, they replace that part. That's not how OBD II is supposed to work. It's why I do all my own work. I don't hold out too much hope they will get it right, especially because it's a Subaru/Kia dealer, but I could be wrong and very happy.

Finding a good mechanic who understands the process of elimination is golden. I do most of my diagnostic work but also have a good Porsche shop that I trust. Good luck!

[Swhitcomb]

Little update. They called and told me they had pulled the connector, cleaned it, reset the check engine light, and test drove it 5 or 6 miles. They said it wasn't misfiring anymore. I went to pick it up around 7. It was running terribly. Missing really bad. Would hesitate severely when the gas pedal was depressed. I handed them back the key and told them it wasn't fixed. I called to check on it this morning and the shop manager said his tech hadn't had time to do a diagnostic on it, and wasn't sure they could fix it. He said they may have to take it to a European Specialty Shop. At this point, that's what I am hoping for. There is a really good one right around the corner from them. I'm sure they can fix it, and hope that in the end that's what they decide to do.

[Jager]

Originally Posted by Jager

Try disconnecting the MAF Sensor and see how the motor runs. Do this just long enough to test, don't drive too far without the MAF Sensor connected.

How does it run with the MAF Sensor disconnected?

[Swhitcomb]

I don't know. So far I've left it in their hands. If it isn't fixed when I pick it up that'll be the first thing I check.

[Swhitcomb]

Well, this dealership is really striking out. I spoke to them early yesterday. They told me they were waiting for the tech to be in so he could run a diagnostic on it. They weren't sure it was something they could fix and may have to send it out. Understandable. They are a Kia/Subaru dealer, didn't expect them to be Porsche experts. He tells me he'll let me know. So I wait unti 330 and haven't heard back from them. I call and am told the guy who knows what's going on is busy and will call me back. I wait until 4:55. Haven't heard a word. I call again. After being on hold for over 5 minutes he tells me they can't figure it out. It's beyond what they can do. They are sending it out to another shop, who specializes in European Cars. This particular shop does mostly exotics Ferrari, Jag, Fiat, Mercedes, etc. and has a really good reputation in this town. Good news there. However, they can't get it in their shop until next Thursday. An entire week with no car. A week I am on vacation and need my car.

[Swhitcomb]

Finally, after over a week, I got it back. The shop that did the work was great. The dealer I got it from, not so great. It turns out it was the MAF. Once a competent mechanic got it, he fixed it in an hour.