P2198
I can’t seem to get rid of mine
changed the AOS
new o2 sensors all round
changed the purge valve under the inlet manifold
new oil cap
new fuel cap
new fuel pump
new coil packs

only mods on the car are sprint booster and miltek cat back

doing my head in

 

See what your fuel pressure is doing. I had a similar thing happening and it was low fuel pressure. Did you replace the fuel filter? Maybe Datalog it if you have a Durametric and one of the super-pro's might be able to tell right away. Markski figured out my issue for me. What a great guy he is! Hope you find the problem. GL. I just bought my first Boxster S today. Hope she is reliable. Peace

 

Thank you for your reply

it was the bank 2 cat that had some pinholes

i took it to an exhaust shop, the chap was a really experienced welder and exhaust fabricator. Applied a new bead of weld around the end of the cat just before the downstream o2 sensor/ before the exhaust shield. These seem to become quite brittle and that was where mine was blowing. The bead was quite thick and pretty much factory looking. Filled any remaining holes.

This Explained the readings above.

I had actually taken it to an exhaust shop prior to all this happening, who supposedly checked for pin holes and told me that it been sorted before I took a trip down the rabbit hole. This put me right off the track of the actual problem.

eventually after throwing money and time at the problem I ran a smoke machine on the topside and in the exhaust to look for air leaks, this gave it away that the first shop hadn’t fixed the problem in the first place.

I wish I had gone to someone reputable the first time around.

congrats on the car !

 

I honestly have never heard that one before. That's great you found the problem. Yayyy!!! Good exhaust guy! Cheers.