Codes 1123-1125-1128-1130

[scooter2]

Hello
New proud owner of 1998 boxster

Well I have these codes come up and I went to good local mechanic (not dealer because they are 4 hours away) and he looked for vacuum leaks, cleaned maf.
aos was changed 3 months ago.
He spent 2 hours and basicly said he is not sure what to look for next.

Any suggestions would be greatly appreciated.

Thanks

[kk2002s]

For me 1128/1130 were from a vacuum leak in hose that connects AOS to throttle body. I created the problem when I did throttle body, tubes cleaning and did not seat and orient it correctly. Changed orientation and it seated, no more codes

[mikefocke]

So you are getting both lean and rich codes on both sides. Sounds like something common affecting the air/fuel mixture causing it to go one way and then over-correct. A signal, a computation or a supply of something.

Assuming the mechanic has correctly looked for leaks in the air intake....

Checked the fuel supply? Filter? Swapped the MAF? Checked the AOS (I know it was swapped, doesn't mean it was done right or hasn't failed)?

How is the mechanic testing? What diagnostic computer is he using? What is his Porsche experience?

[JFP in PA]

Originally Posted by scooter2

Hello
New proud owner of 1998 boxster

Well I have these codes come up and I went to good local mechanic (not dealer because they are 4 hours away) and he looked for vacuum leaks, cleaned maf.
aos was changed 3 months ago.
He spent 2 hours and basicly said he is not sure what to look for next.

Any suggestions would be greatly appreciated.

Thanks

It is unusual to say the least to get both rich and lean mixture codes at the same time.

Two questions: What type of scanner did your mechanic use to obtain these codes, and did he test for O2 sensor cycling? It is not unusual for a non Porsche specific diagnostic system to throw a strange mix of codes that make no sense, so if he used a generic system, get it rescanned on a Porsche system (PST II, PIWIS, or Durametric).

[thstone]

Rich and lean codes are almost meaningless.

Clear codes. Drive. Got CEL? Immediately stop and check codes with Porsche specific tester. Fix the problem for the first codes to be reported.