Smog Purgatory on 2002 Boxster S

[frankyzambony]

​​Hello fellow BoxsterFarians. I am stuck in Smog purgatory. Of the 5 "ready" attributes one will not come ready (which prevents California smog stations from being able to run a smog test). The attribute that is giving me trouble is the Secondary Air System test. When I started on this journey I had a few CEL codes that needed to be dealt with. I was throwing P0410 and P0411 as well as P1128 and P1130's. To add some excitement I was also getting P1115 codes occasionally. I tackled the P1115 error first. (Durametric translation - Porsche fault code 13 Heating Power O2S ahead of cat c bank 1). I swapped the two front (ahead) O2 sensors and drove it around a bit. Soon I had a similar error but it pointed to bank 2. So the error followed the sensor. I replaced that O2 sensor and the P1115 error is gone. Next was the P1128 and P1130 errors. Everything I read pointed to the Mass Airflow Sensor. Swapped that out, now all my errors are gone. Ready for Smog test right ? Well not so fast... Once the CEL codes are cleared, all 5 smog ready attributes change to the FAIL state. In order for the attributes to transition back to the PASS state one must drive the car through a cycle. There are tons of forum postings on what makes up a drive cycle so I won't go into that here. Long story short - I have driven through 4 controlled drive cycles and that pesky Secondary Air attribute will not change to pass. I have no other codes showing and things seem to be stuck. Some postings indicate that a weak O2 sensor can prevent the Secondary test from running to completion leaving one in Smog Purgatory. I have attached a Durametric log graph from my latest coldstart. (My Secondary Air pump appears to run fine and turns off after 60 seconds or so). If you look at the graph, the O2 sensor voltage AHEAD of cat (Bank 1 and Bank 2) appear to react differently during the time the air pump is running. Bank 1 (RED Graph) is the new O2 sensor. Bank 2 (BLUE Graph) is an O2 sensor that has not been changed. Should these two sensors track more closely? (as the two AFTER cat ones do ?) Could this difference in O2 Sensor performance be a cause of my Secondary Air test never finishing ? Would love to hear some opinions from this forum. Thank you, Frankyzambony Livermore California

[Chuck W.]

Post 8 of the below thread may help you.

Secondary Air test monitor won't complete

[steved0x]

If it turns about to be O2 sensors, prices seem.to be coming down with a few new direct fit brands, check Mike Focke's web page for Bosch part numbers and then check pelican, amazon, and rockauto

[frankyzambony]

Updated chart showing only the POST cat sensors.

[jb92563]

The post cat sensors Voltage are supposed to show a low amplitude wave close to a straight line.
The blue line seems to indicate a sine wave similar to what the precat sensors would be reading meaning that the cat is not working.

Its also a little erratic so perhaps you have not gotten the cat hot enough.

I'd try a few more minutes of vigorous driving or highway to make sure the cats are hot enough to be working properly.

If there is no improvement, it means that the cat is no longer functioning efficiently.

I have just dealt with a similar issue but had the Cat 420/430 code on my 2001 S with 75k miles.

If you resolve the other codes first and the problem persists it may need the cat replaced.

Normally a cat will last for the life of the car, but they can fail by becoming plugged/fouled with oil/carbon deposits, ceramic element can be broken up or the cement holding the element in place can fail/leak.

Replacing the cat with a used one from ebay (~$250) solved the issue in my case but I was not getting the other codes you are having.

My defective cat had its element come loose inside the cat and presumably allowing enough exhaust gas to bypass the element that it produced the CEL codes.

[JayG]

I had the EVAP monitor take a long time to reset. It was finally after about 3 weeks of trying did I finally get it to reset

here is what I followed
Drive in 10 minute cycles 1400-2800 Rpm in 5-6 gear as slow as you can drive in light traffic.
If you stop or go out of RPM range the cycle resets the timer.
After 5-6 cycles you will probably have it.
For evap you must have 1/3-2/3 of a tank of fuel.
Start the car cold and let it idle for 10 minutes with lots of accessories on. (lights, A/C or heater)
Do the same at the end of the drive cycle.

[Chuck W.]

I feel for OP. My wife's Mini Cooper was missing the O2 flag and wouldn't pass smog. I did a bunch of drive cycles and couldn't get it to reset. So, I came up with the brilliant idea of disconnecting the battery and resetting all of the flags and starting fresh. After another round of multi drive cycles I still had O2 flag along with the EVAP flag. In an act of frustration I took the Mini onto Mulholland and flogged it. After some very spirited driving what do you know, both reset. Maybe the car know I was pissed.

[frankyzambony]

Happy new year !

So I went outside this morning to get one more record of the coldstart and to my surprise the ready status had finally flipped.

(4 controlled drive cycles plus 1 short drive cycle last night of < 3 miles)

Attached are the logs from this latest startup, things look much better however I have not changed a thing.

The good news is I will be heading to the SmogMan tomorrow and hopefully will pass Smog.

Thanks to everyone that chimed in for help...