Interesting CEL Codes

[roger_mck]

Last year I was getting codes 1123 and 1125, lean threshold on all cylinders. Replacing the MAF solved the problem for about eight months. This is a '99 2.5.

1123 and 1125 recently came back. I added some fuel system cleaner to a tank of gas, reset the codes, and drove about 300 miles w/no CEL. Then the CEL came back except is was codes 1124 and 1126, rich threshold. I reset the CEL and the same codes came back within a few days.

I was wondering if anyone had ideas about what might cause this combination of codes? I suspect that having both a too rich and then too lean condition might be a good clue.

Also - the oil filler tube - is it 'normal' for it to be coated with a fair amount of oily grime? Not all over the engine, pretty much just on the outside of the plastic section of tubing near the clamp? It didn't seem to me like there was an obvious problem but it also didn't look quite right.

It's about time for new plugs and the fuel filter is about 25,000 miles of age. Guess I'll do those at any rate and see if anything changes.

Thanks!

[roger_mck]

Haven't made much time for the Boxster lately but I did get the plugs changed. I found both Beru r6 336 and r6 310 plugs, I'll assume for now they're equivalent. But I never had seen a plug where the gap appears set below the base of the center electrode. Again for now I'll just assume that's the way Beru plugs are configured.

[Rom]

Possibly a faulty O2 sensor? Considering the variable error messages (lean then rich)...

Thanks!

Shash

[insite]

Also - the oil filler tube - is it 'normal' for it to be coated with a fair amount of oily grime? Not all over the engine, pretty much just on the outside of the plastic section of tubing near the clamp? It didn't seem to me like there was an obvious problem but it also didn't look quite right.

do you mean within the engine bay? it sounds like you may have a vacuum leak. this can cause the error codes you describe. on a '99 2.5, my money's on the oil filler tube itself or the oil separator bellows. i'd carefully inspect both for leaks & replace if required before replacing anymore sensors.

Edited March 23, 2006 by insite

[roger_mck]

Yes - there is the (first) tube that runs from the trunk to near the throttle where it is clamped to another that goes down behind the engine. The first tube, near the clamp, has a uniform coating of oil on the outside of it. It starts near the union of the two, extends back towards the trunk, and tapers off to nothing after about a foot or so. But it almost looks like it 'sweats', there is not an obvious crack or break in the tube.

I appreciate your advice. I've been going back and forth trying to figure if it is the tube itself or the union between the two that could be a problem. There is also a tiny amount of oil on the engine, right under the union. Maybe a new filler tube would do... don't think I have any hi-temp duct tape!

[jcorallo]

Yes - there is the (first) tube that runs from the trunk to near the throttle where it is clamped to another that goes down behind the engine. The first tube, near the clamp, has a uniform coating of oil on the outside of it. It starts near the union of the two, extends back towards the trunk, and tapers off to nothing after about a foot or so. But it almost looks like it 'sweats', there is not an obvious crack or break in the tube.

I appreciate your advice. I've been going back and forth trying to figure if it is the tube itself or the union between the two that could be a problem. There is also a tiny amount of oil on the engine, right under the union. Maybe a new filler tube would do... don't think I have any hi-temp duct tape!

Hi - dragging this topic up - did you replace the tube in the end??

Cheers,

Jules