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2002 325iT can't receive a CA SMOG cert because some of the emissions systems refuse to make themselves known. Car runs excellent, 161K miles.
Had a couple of CEL codes (now fixed) a couple of weeks ago, but these systems are showing incomplete. (Note: I have no idea if they read properly before I fixed and cleared the CEL codes, and then had the battery disconnected for an afternoon.) They're not reading bad numbers - they're not reading anything at all:
Secondary Air System (pump works properly, turning on - and then off - at cold start-up)
Evaporative System (new fuel cap & purge valve, correcting the P0444 code - can I assume this pertains to the evap system?)
O2 Sensor Heater
And today, a new one didn't come on (reporting incomplete):
Catalyst
No other CEL codes current or pending. The SMOG guys told me to just drive the car and systems should all come online soon. BMW sent me a print-out of how to get the systems to come on (start cold & idle for 3 minutes for the secondary air pump, etc). But it's been weeks and a few hundred miles of assorted driving conditions and nothing has changed.
Last resort is I take it to BMW and they confirm that everything is working as it should, and I take that confirmation to a SMOG "referee", who should pass it. But that will cost me around $190 for the BMW diagnostic.
I thought maybe the secondary air pump wasn't coming on, and therefore the other systems, dependent on O2 readings from the cold start, can't come online. But I checked and the air pump works properly. The secondary air valve - I have no idea, but if it's clogged or not opening, could that be stopping the secondary air system to not report, and then domino-effect for the aforementioned sensors?
Any advice from the crowd? Drive it more? Be patient? Is this unusual - 300 miles and two weeks should be enough? Reeeeeally starting to annoy me...
Last edited by filmy; 08-15-2018 at 12:17 AM.
Member
Find a reputable indie shop via www.bimrs.org. Head over to E46Fanatics and search for threads on readiness monitors in which jfoj has commented.
Jbird
If all that needs to be set is cat monitor, this is the drive cycle to use. No quick acceleration, 40-60 mph, Rpms stay below 3,000, no braking, while driving include short periods of coasting, test drive should last 20 mins. My Customer just set his in his e46 m3 and he had been trying to set it then I told him what needs to be done. Though I can't find an explanation for the specifics, I think has to do with flow rate thru the cat and the cat maintaining correct temperature. You may have to do this a couple of times but it has always worked for me.
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A LOT of great information there, and found very similar symptoms. Thanks, Marco!Originally Posted by MarcoZandrini
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You’re welcome! We’re all in this addiction together.
Member
Update - finally got them! In my case it was two things: SAP valve needed the vacuum lines replaced (more of a b!tch to get them onto the valve at the rear of the intake than you'd think...) My pump was coming on as it should, and I could feel vacuum coming from the electric manifold valve, but when the engine was off I could both blow and suck air through the vacuum line - and there's supposed to be a one-way check valve @ the intake manifold, so that shouldn't be possible. There was still vacuum coming on for cold-starts, but apparently not enough to open the exhaust valve. Once *that* was fixed (and cold-started twice) the system came online as "completed". I also have a suspicion that the SAP system was working well enough that it would have come online if the O2 sensor (right next to the valve) could read the fresh oxygen being pumped in (see below), so a domino-effect here. But replacing that vacuum line probably fixed an intake manifold vacuum leak as well.
Secondly, my #1, bank 1 O2 sensor was barely finger tight. I figure the previous owner didn't have the tool to tighten it fully. Tightened it, but got no love from the sensor heater system; changed it out for a new Bosch, more cold-starts and correct drive cycles, and the both heater and catalyst came online as completed. The only system not coming on yet is the EVAP, but the SMOG place told me that's the only system fail they are allowed to pass a car with.
I have to add that I worked through these problems with an OBDII bluetooth reader and the Torque app on my Android tablet. I didn't know that Torque could show me system readiness (or lack of readiness) which saved me a *ton* of time from going back and forth to the SMOG place to plug it in and read the sensors' readiness.
The drive-cycle information can be confusing, because they're a waste of time if there's something wrong with the sensors/systems, and it seems the drive-cycles don't work. But once the systems are repaired and proper, the drive-cycles work as they should: 4 minutes @ nonstop 30mph brought the O2 sensors on; 15-minute highway drive at ~55mph brought the Catalyst system on.
Member
Dump the Torque app and get OBDFusion. The head back ti E46Fanatics and find threads in the app in which jfoj has commented. He’s the guru.
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