Codes P1128 and P1130

[newlife]

Hello,

I ‘ve had success fixing codes P1128 and P1130. Because of Wayne’s book and the advice on this forum I have learned so much and wanted to pass it on. I purchased my 2000 S Boxter S from an acquaintance two months ago. When I took the car in for the pre-purchase inspection, the mechanic said all was well, but referred to two codes that came up. He referred to the codes as “soft codes”, and were no big deal. So, at the time I had no idea what that meant and did not ask. Other than that, the car came out excellent.

So, while trying to get the car smogged, my CEL comes on and so it failed the test. And, I had three monitors that were incomplete, and the codes P1128 and P1130 were present. After some serious research on smog inspections and reading Wayne’s book and this forum, I learned that codes P1128 and P1130 were emissions related. So, I looked into the service records of the car, which the prior owner had. This was a huge advantage to have the service records. Turns out that 2 of the 02 censors were replaced in 2009 and the other two were replaced in 2011, a few months back. The P1128 and P1130 codes were present back in 2009 but no mention in 2011. Also, there was no record of any cleaning or replacing of the MAF. Wow, I took notice of this! I also began to study the inter-relationship with the MAF and the O2 censors. Turns out there is one ! I am puzzled though as to why the Porsche mechanic never address the MAF sensor. It was never cleaned or replaced. And neither was the throttle body. At the time of purchase my Porsche had 39,800 miles on it.

So, I cleaned and re-installed the MAF sensor, I cleaned the throttle body, I replaced the air cleaner and added Techron to my gas tank. I go out for a drive on Japatul Valley Road in Alpine 91901. The car sounded awesome and I could detect / feel it was running smoother. I also had the top down for the first time. I had cleared the codes before I did the maintenance to the car. I checked the codes after about 60 miles of awesome mountain driving. There were none, and they did not come back.

I took the car down to the smog guy and it past smog and so far, there are no codes. Thanks to all the postings and Wayne’s advise this was all possible.

Rod

[Dale_K]

Good for you. I fought with some of the same codes and eventually fixed them with a new MAF sensor. Cleaning didn't work for me and there were no codes specifically related to the MAF but it was truly bad because the fuel trim reading changed dramatically after putting in the new sensor.

[newlife]

Yeah, I compared my failed smog check with the passing smog test and there were definitely changes in the CO2 and O2 readings.

Rod