P0446, p1124, p1126 cel
 

After six years of near flawless service my Boxster is having some trouble. Two weeks ago I noticed the car was occasionally idling a little rough when stopped. Mechanic said it was the MAF, replaced it. Got the car back and noticed it had trouble turning over every 5-6th time, mechanic said it could be the starter, maybe AOS related.

I then got a CEL P0446 (EVAP Canister Shutoff Valve (Function) - Below Lower Limit). This evening the car did not start the first try. It turned over the second time but it stalled after idling for 30 seconds. I finally got home and have two new codes P1124 (Oxygen Sensing Adaptation Area 1 (Cylinders 1 - 3) - Rich Threshold) and P1126 (Oxygen Sensing Adaptation Area 1 (Cylinders 4 - 6) - Rich Threshold). I just had the MAF replaced.

I am thinking it could be dirty fuel injectors. Any thoughts on this? My mechanic is only two miles from my house, is it safe to drive the car to him, or should I have it towed.

Thanks!
-Rick :cheers:

P1124 & 1126 (both banks):

Fault condition:
Fuel/air mixture so lean that sensing has reached its rich threshold.

Potential fault areas:
– Intake air system leaking
-- Air is introduced past the MAF causing the mixture to be more lean
– Fuel pressure too low
-- Not enough fuel to meet demand causing the mixture to be more lean
– Volume supply of fuel pump too low
-- Not enough fuel to meet demand causing the mixture to be more lean
– Fuel injectors fouled
-- Not enough fuel to meet demand causing the mixture to be more lean
– Exhaust system leaking
-- When the exhaust system has leaks before the front O2 sensor will cause the O2 sensor to report a lean condition (excess oxygen i the exhaust)
-- Although the service info didn't mention the MAF as a potential fault area, I would test that also.

P0446:

Potential fault areas:
-- Purge air line blocked
-- Flow resistance of EVAP canister is too high
Note: fix other codes first before tackling this one.

Regards,
paul...

I have now had the MAF and AOS replaced, yet the P1124 and P1126 codes have come back once or twice over the last few months and it comes back in minutes if I reset it now.

In the last few days the idle is rough 50% of the time, and with the AC on, when I push the clutch in the RPM drops to 700 before recovering and is just on the cusp of stalling, like letting off the clutch without enough gas. Additionally, every so often, particularly when I shut the car off I hear a hydraulic type compressor sound from in front of the passenger door. Lastly, I could swear that the car is lagging a split second between when I put my foot down and I get power, even at high RPM's.

Any thoughts on what this is? Fuel pump and air leak? I want to try and get an idea of the problem before I send it to the mechanic.

Thanks! :cheers:

Can't say that this'll fix your problem, since your symptoms of rough idle and RPMs dropping when you disengage the clutch is not what I was experiencing. But for me what eventually made my P1124 P1126 and P0446 codes go away (at least, so far) is replacing the tank vent valve, 996-110-129-06, that's under the driver's side intake manifold.

Starts, Fires Up, Dies... - Pelican Parts Technical BBS

Check your gas cap. If the sealing o-ring is cracked or damaged you could get all 3 codes. If the gas cap is ok, it still looks like a gas tank vent issue. Torn vacuum line, evap ck valve, etc.

Exact same codes on my 996...regeneration valve

How is everyone seeing these codes and stuff??? Is there something you buy to plug onto a computed or.something???

Thanks for the relies, I always try be as knowledgable as possible to make sure the mechanic doesn't try anything. You can pull codes with a $20 reader from harbor freight, then you just google the codes.

The ECU stores failure codes in memory, known as OBDII codes, which can be read out with an electronic reader that plugs into the OBDII port (purple, if I remember correctly) under the dash right above your left knee. OBDII readers are available at any auto parts store for $35 and up.

Let's not forget about the Durametric system. If you have the coin this is the way to go. You will also need a laptop.

Diagnostic Tool for Porsche | Durametric

Jäger,

I've given up recommending the Durametric tool as most people, unfortunately, don't have the diagnostic info or the experience to understand what they're looking at or looking for.

Regards,
paul...

+1
For serious gearheads with the skill and experience to use it, Durametric is a great tool. For the average Joe diagnosing a CEL to decide if it's a DIY or Pro repair...
http://www.amazon.com/Actron-CP9125-PocketScan-Code-Reader/dp/B0007LEG2K