Engine Check Light: P1128 & 1130

[Lowski]

I had these two codes in the past.

http://986forum.com/forums/boxster-general-discussions/72288-p1128-p1130-running-fine-turned-into-barely-running-engine.html

The short version is I had a bad MAF. To get to that conclusion I ended up monitoring the fuel trims. A Durametric or other scan tool that can read fuel trims values will tell you if have a vacuum leak or not. If you can determine if you have a vacuum leak or not then you can focus on either fuel or air as thstone suggested.

Originally Posted by Jonconsean

I told I bought it new at Autozone.

What brand of MAF did you buy? You may have gotten a bad or cheap one?

The general consensus I found online was it should be Bosch. If I remember right the Porsche branded MAF sensors are Bosch with a Porsche stamp. Some on the forums state that Porsche hand picks the betters MAFs from the lot for the Porsche branded ones. I can’t confirm or deny this. The moral of this story is maybe you Autozone MAF may be bad out of the box. It wouldn't be the first time a new sensor failed.

Originally Posted by Jonconsean

He is charging me $400 for a new MAF sensor.

$400 to change a MAF is way too high in my opinion. The sensor is about $200 bucks for a Bosch. It takes longer to get to the engine then it does to change the sensor.

[paulofto]

Originally Posted by Lowski

$400 to change a MAF is way too high in my opinion. The sensor is about $200 bucks for a Bosch. It takes longer to get to the engine then it does to change the sensor.

What he said . . . . . . Changing the MAF is a 10 minute DIY. Just need the proper tamper proof torx socket.

[1PorscheBoxster986]

When I had the issue with bad MAF sensor, I didn't buy a new one. It's crazy expensive. I purchased a used MAF sensor making sure it was the latest revision. It's the Bosch 98660612501 a few years back. There might be a new revision out but that was the latest one for my 01 at that time. I bought it off eBay and the seller was (qualityporscheparts) who I have had good luck with several times.

I tried cleaning the MAF sensor & throttle body like you with CRC products but CEL came back on after a quick drive. It cost me $40 and it's been running great since. I'm not sure that it matters but the used MAF sesnor was listed with around 30K miles of usage at the time.

Changing the MAF sensor requires you to have a security torx bit. I had to buy a cheap set on eBay that cost like $8. It came with magnetic security torx bits among other bits that are not common. I don't recall resetting anything but if I did, I used a cheap OBD2 bluetooth with TorquePro smartphone app. It's a very easy job like paulofto said. You just have to put your softtop in service mode and get access to the engine. You will see it.

[piper6909]

Originally Posted by Lowski

The moral of this story is maybe you Autozone MAF may be bad out of the box. It wouldn't be the first time a new sensor failed.

I've had so much bad luck with Auto Zone parts that I refuse to go there anymore unless the closest NAPA or Advance Auto is 100 miles away. Or if it can wait, I'll order the part online.

[Jonconsean]

I changed the MAF with a OEM Bosch MAF sensor and after clearing the codes. They came back. So I am back to the drawing board.

[Jager]

Check your Air Oil Separator. Remove the oil fill cap while the engine is running. Is the cap hard to remove? Is there a lot of vacuum from the oil fill tube (does it sound like a shop vac)?