Codes 1128 - 1130 on 2002 boxter

[yimmy149]

Try removing the oil filler cap in the trunk with the engine running. If it is difficult to remove and/or makes a sucking sound - you probably have a failing AOS.

-james

[tony0214]

Originally Posted by yimmy149

Try removing the oil filler cap in the trunk with the engine running. If it is difficult to remove and/or makes a sucking sound - you probably have a failing AOS.

-james

thanks i'll try that

[robmints]

I have the same codes, starting the shotgun method. First looked/listened for obvious leaks. Cleaned the maf sensor. Did not know about the oil cap sucking method, but ordered an aos and tube from Sunset, yet to receive. But I'll let you know what works if I ever find it. The durametric thing works fine, but since I don't know what normal is I don't know what to look for and if it would even help.

[S3adrag0n]

How long does sucking air from the oil cap until total AOS failure? I've notice my 2000 w/68K mile sucking oil but no indication or smoke from tail pipe(yet). I did notice an O2 Sensor code 4-6 times during the last 10K mile. It would come on for a couple minutes to a day then off for 2-6K mile without ever coming on again. I've own the car for over two years now and had the O2 light problem when I bought it.

I feel I had this problem (O2/failing AOS) since I own the car and have been driving with a failing AOS for that last 10K/3yrs. Could I have been lucky with a failing AOS what hasn't gotten bad yet or could I have a different problem?