P1130 & Smoke At Startup - AOS? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

DMage · 06-20-2015, 04:45 AM

Threw a P1130 code the other day, thought it would be difficult to track down the issue.

For reference, P1130 = Oxygen Sensing Adaptation, Idle Range, Bank 2 - Above Limit.

I've driven the car about 300 miles since purchase. Just recently cleaned the MAF, throttle body, changed oil, replaced spark plugs & tubes, and filters. Figured it was something I did with the MAF cleaning that caused it. I did not throw the corresponding P1128 code.

Cleared the code out and was going to take it out for a drive this morning to see if I could get it to retrigger, possibly with the P1128 this time. And was going to try to pull the oil cap off when running. However, upon startup got a nice big cloud of smoke. Assume at this point its safe to say the AOS needs replacing, and a good chance it is the cause of the P1130?

Have the car parked, not wanting to drive it and cause any serious failure.

Flavor 987S · 06-20-2015, 04:54 AM

A puff of smoke, on cold start up, is normal on these cars. Did the smoke quickly clear? Need more info.

DMage · 06-20-2015, 05:21 AM

It was a pretty big puff, and I turned the car off when I saw it. I haven't had any smoking on the car that I've noticed previously. I did let it clear out and sit for 10 mins for the oil level sensor to reset. Restarted and no smoke and the oil level was two from the top full line (3 bars unlit).

I was going to take it in for a smoke test for the P1130, as I wonder if its a cracked oil filler tube per some comments I was reading on other P1130 threads where there was not a corresponding P1128, but the AOS was also mentioned as a culprit. Maybe I am just jumping to conclusions.

On the second start (without smoke) I checked the oil filler cap. I was able to remove it and hear the vacuum, and the idle stumbled. Also I should mention after clearing the P1130 code the idle was rough/stumbled for a bit, I assume it was the computer relearning the mixture. But, now it is idling fine.

Also, car is a 2000 S, with almost 83k miles. AOS is probably original, no documentation to show its been replaced.

crooster · 06-21-2015, 07:07 AM

My AOS failed recently. I got both P1128 and P1130 but I had significant vacuum on the oil filler cap, so much I could barely remove it.

Timco · 06-21-2015, 07:28 AM

Scavenger pump?

I've seen a pretty decent cloud before, just one big puff. (But that was my younger days....)

DMage · 06-21-2015, 07:39 AM

Quote:

Originally Posted by crooster

My AOS failed recently. I got both P1128 and P1130 but I had significant vacuum on the oil filler cap, so much I could barely remove it.

Hmm, OK, then I'll wait to see if the P1130 pops back up by itself. Wonder if its a crack in the oil filler tube then. Going to poke around later. Thanks!

Steve Tinker · 06-21-2015, 10:20 PM

If you had a crack in the oil fill tube, the idle would stumble just the same as when you took off the filler cap, and code 1130 is just for bank #2 .

A good candidate for smoke on startup is if you started the engine for a short period (say to move the car) and then switched off. I get the smoke if I move the car to wash it and then move it back into the garage, The next cold start = smoke.

Another peculiarity (maybe just on my particular car) is that it tends to smoke on startup just before the oil needs changing - not every time (one in ten cold starts) but maybe its just telling me to get the old out and new in.....

shacky · 06-27-2015, 04:25 PM

Quote:

Originally Posted by Flavor 987S

A puff of smoke, on cold start up, is normal on these cars. Did the smoke quickly clear? Need more info.

I just had this happen for first time - at least that I noticed. I was away for 4 days. Started her up then noticed big puff of smoke blowing sideways (she was in driveway : (

Nothing afterward.

DMage · 06-29-2015, 05:32 AM

Well the P1130 came back, no associated P1128 yet. However, also got a P1115 along with it this time. Sounds like its time to replace the pre-cat O2 sensors, not that I think it is related to the P1130 however from looking at details online.

Going to watch the O2 sensors on the Durametric when I get home today. Had the Durametric up monitoring the MAF and the numbers appear to be within spec at 700 RPM and 3000 RPM no load.

MAF was reading 12-13 kg/h at idle, and 56-57 kg/h at 3000 RPM no load.

No smokey startups in the last 5 starts, assuming the first one I got was just due to a previous cold start short drive.

DMage · 07-02-2015, 08:53 AM

Durametric showed RKAT at 4 and 3.8 at idle. Not sure what it maxes out at, assuming 4.5 which seemed to be the highest reading I had at one point. Issue appears to be with both banks, and its just that the P0128 hasn't tripped yet due to whatever inherent delay in the system.

Took the MAF out again as I just cleaned it a few weeks ago. Looking it over this time noted a 'REMAN' sticker on it. Did some digging and couldn't come up with which company it was. However, in my research I found that my car SHOULD have the earlier MAF sensor, and the REMAN was of the later style (at least from its plastic casing). Have a sneaking suspicion the previous owner may have had an independent shop replace it and they were not aware of what they were doing - just went with the cheapest option.

Picked up the MAF that *should* be correct for the car. The Idle is now at 14-16 kg/h and 3000 RPM at 60-62 kg/h, so 15-20% off at the low end and 5-10% off at the high end. Wondering if this is my ultimate problem. Going to run with the older style MAF for a bit and see if this truly was the case.

Also, picked up two pre-cat O2 sensors to replace the existing, as one looks generic (non OEM) and the other looks original. Hope this will tackle the P1115 code. For anyone interested, RockAuto has AIRTEX / WELLS Pre-Cat sensors for $41 a piece on clearance (5% off code floating around online too) and they are just Bosch purchased and reboxed.