How do you know P1130 is MAF not O2 sensor

[brucenoah1956]

I have repeated P1130 codes that happen every couple of weeks just as the engine warms to normal operating temp if I get stopped at a traffic light. I erase the code and CEL stays off for weeks at a time. Conventional wisdom on this board is that code is set by MAF, not due to a problem with O2 sensor. I cleaned the MAF two weeks ago, but the light came on again this morning. Car runs perfectly with no perceived problems other than the CEL.

Car is a US Boxster S, 2001 model built in Finland with Tiptronic.

1. How do I further diagnose to determine if it is MAF or is actually O2 sensor?

2. If it is the O2, can someone provide a photo of the location for the sensro that sets P1130 and replacement instructions.

Thanks,

Bruce

[mikefocke]

Causes of an 1130

Caused by the ECU feeling it needs to adapt the fuel/air mixture beyond its specified ranges. Too rich or too lean.

First clear up any other codes.

– Incorrect signal from MAF sensor

– Intake air system leaking

– Fuel pressure too low or high

– Volume supply of fuel pump too low or high

– Fuel injectors fouled or leaking

– Exhaust system leaking

What you can do: Check exhaust system for leaks ahead of 02 sensor. Check Intake system for leaks. Dump a bottle of Techron in the full gas tank.

What a shop with proper equipment can do: Check MAF signals. Check fuel pump pressure. Check injectors for leaks.

[brucenoah1956]

If it was a vacuum leak why do I only get a code for one bank? Is it possible opposite bank code P1128 is pending but hasn't set yet?

[pk2]

Were it a vacuum leak around and injector as mikefocke suggested....

PK

Edited October 13, 2009 by pk2

[mikefocke]

P1130 isn't bank specific.

If you notice the causes the 7.2 DME manual lists, they all can affect both banks simultaneously.

There are 2 1130 codes, A and B. But the difference is not which bank but which end of the adaptation range is being exceeded. I condensed both into a single list of causes.

[brucenoah1956]

P1130 isn't bank specific.

If you notice the causes the 7.2 DME manual lists, they all can affect both banks simultaneously.

There are 2 1130 codes, A and B. But the difference is not which bank but which end of the adaptation range is being exceeded. I condensed both into a single list of causes.

Mike,

I'm confused. The 7.2 DME codes on this website shows:

P1128 Oxygen sensing adaptation, idle range, bank 1

P1130 Oxygen sensing adaptation, idle range, bank 2

Can you provide more insight?

Thanks.

[Loren]

P1130 Oxygen Sensing Adaptation, Idle Range, Bank 2 – Above Limit

or

P1130 Oxygen Sensing Adaptation, Idle Range, Bank 2 – Below Limit

Possible causes:

– Incorrect signal from MAF sensor

– Intake air system leaking

– Fuel pressure too low

– Volume supply of fuel pump too low

– Fuel injectors fouled

– Exhaust system leaking

The first two are the most common. Usually either a bad MAF or a an air leak like a loose hose, cracked AOS (and or bellows), cracked oil fill tube, or even a bad o-ring seal on the oil filler cap.

[yuyokatana]

I have repeated P1130 codes that happen every couple of weeks just as the engine warms to normal operating temp if I get stopped at a traffic light. I erase the code and CEL stays off for weeks at a time. Conventional wisdom on this board is that code is set by MAF, not due to a problem with O2 sensor. I cleaned the MAF two weeks ago, but the light came on again this morning. Car runs perfectly with no perceived problems other than the CEL.

Car is a US Boxster S, 2001 model built in Finland with Tiptronic.

1. How do I further diagnose to determine if it is MAF or is actually O2 sensor?

2. If it is the O2, can someone provide a photo of the location for the sensro that sets P1130 and replacement instructions.

Thanks,

Bruce

I had the same issue with code 1130, after I blew the air box I guess the MAF got dirty. I cleaned the MAF with MAF cleaner and Kaboom cel gone. Try it!!!!

[Speedobird]

I have repeated P1130 codes that happen every couple of weeks just as the engine warms to normal operating temp if I get stopped at a traffic light. I erase the code and CEL stays off for weeks at a time. Conventional wisdom on this board is that code is set by MAF, not due to a problem with O2 sensor. I cleaned the MAF two weeks ago, but the light came on again this morning. Car runs perfectly with no perceived problems other than the CEL.

Car is a US Boxster S, 2001 model built in Finland with Tiptronic.

1. How do I further diagnose to determine if it is MAF or is actually O2 sensor?

2. If it is the O2, can someone provide a photo of the location for the sensro that sets P1130 and replacement instructions.

Thanks,

Bruce

I had the same issue with code 1130, after I blew the air box I guess the MAF got dirty. I cleaned the MAF with MAF cleaner and Kaboom cel gone. Try it!!!!

Hi Bruce - I saw somewhere in the forum that we have to be careful in selecting which cleaner to use because some MAFs have coating inside. Can you tell us which cleaner you used for this? Thanks,

[mikefocke]

They make a special MAF cleaner...

CRC Mass Air Flow Sensor Cleaner...Autozone or almost any other shop should have it.

The fault is seldom with the sensor....

http://mike.focke.googlepages.com/checkeng...ssairflowsensor

[Jacob Hernandez]

Was there ever a fix to this? Currently having this issue with p1130 only. 

[JFP in PA]

Read Loren's post above, it covers all the possible issues.