CEL w/ p1126 & p1133

[lvboxster]

stock 2000 boxster - 5 speed - 85k miles -

> oil seperator died -- smoke on start up for a few days, then got much worse and became cartoonish

> replaced oil seperator, oil filler tube, oil filler cap o-ring, fuel cap, and dip stick o-ring -- while under car, I saw oil leaking out of seam where exhaust header pipe meets its mounting flange. Obviously oil going through cats too.

> ran car for a few days with no problems. all fault codes cleared and no more oil issue

> about one week later started getting CEL w/ p1126, p1133, p0507, p1128 rough idle and stutter/choking immediately after start up with any load on engine... ok after about 30 seconds of warm up -- CEL on/off every couple days, seeming to correspond with day/night driving habits. Las Vegas heat may be an issue here. CEL seemed to come on if driven regularly during day time and turned off if driven mostly at night. Don't know if it's related.

> replaced all o-rings and inspected all plumbing on breather/seperator system. replaced breather/pressure relief doohicky on left bank and one spark plug well sleeve and it's o-rings. Car runs smoother and pulls stronger now. CEL off after a couple days.

> car now runs really well, but every couple days i'm getting the p1126 and p1133 CEL -- black soot spots are starting to build up on header mounting flanges where pipes connect. I'm thinking that I've got small exhaust leaks there that are throwing off the pre cat o2 sensors and effectively screwing up the fuel adaptation

> any advice on my issues would be greatly appreciated.

[Chris_in_NH]

it might just be the rest of the ingested oil working its way through the engine. i'd keep an eye on the codes and give it another week. maybe a bottle of Techron, too.