This is a California problem - My 2004 Cab is due for registration and smog check. Turns out I had just replaced the battery and so some element of the smog check is coming back as "incomplete."

The guy working the smog shop said to drive 25 miles at 55MPH and I would get a valid reading again. Well, I drove 50 miles of city traffic and the smog test still rates an "incomplete."

The dealer "never heard of this problem" and can't offer a solution. The smog test house's recommendation of 25 miles at 55MPH doesn't seem to work either. Any thoughts here?

 

Your dealer is ignorant...this is a common problem with a battery swap and then trying to smog in California...the new Regs use the obdII port to check for a readiness reset....your car can be running perfectly and would pass smog check the way they used to do it with the sniffer...but now they check for a readiness reset which can be a real problem after a battery change....this can be easy or very difficult to accomplish....there is a very complex procedure to getting the ecu to pass the self test...you need a tech that knows the procedure...you can borrow or buy a scan tool and try to do the procedure yourself and you might get lucky...I drove over 250 miles and still didn't get a readiness reset...have your dealers service manager or master tech call the Porsche dealer in Fresno and ask for their Porsche master tech Jeff....he knows the procedure....I got screwed because I had originally asked specifically for Jeff to work on my car because I knew he was familiar with the problem and the A-hole dealer had someone else work on my car and he could not get it done....when I noticed on my invoice that the tech that worked on my car was not Jeff I complained to PMNA and the dealer called me and asked me to bring in my car and Jeff would get the readiness reset and there would be no charge...don't let the dealer tell you that you need to replace the cats or the sensors...if that was the problem you would have a check engine light, which I assume you don't...good luck as I know how frustrating thus can be...thank you Kalifornia

 

Once in a while I have to clear a code in my Turbo (misfires at cold engine start) and used to have a converter code with my Boxster which required clearing. Of course clearing the code also resets all the readiness monitors to incomplete.

What I found a number of times is a 30 mile drive from home to office had all the readiness monitors set to complete.

The drive is nothing special. Just a cold start, a moment or two of idling (though often I clear the code after I've started the engine) then I drive city streets a 1/2 a mile or so to the freeway then around 28 miles via freeway at anywhere from freeway speeds to some stop and go driving to where I get off the freeway and take city streets the remaining distance to the office. Total length of trip is 30 miles or thereabouts.

About all I can say is I avoid thrashing the engine -- really traffic conditions are not condusive to hooning around in the car anyhow -- and that's that.

My dealer is very aware of this readiness monitors not set issue. It sees, the techs see, a number of vehicles that get used very infrequently. In some cases the owner leaves the car and the tech drives the car around to set the readiness monitors then smogs the car.

About all I can advise is go to an autoparts store and buy an OBD2 code reader/data viewer that also lets you check that readiness monitors are all set and connect this to the car's OBD2 port and drive the car normally until you see the monitors set then swing by the smog shop and have the car smogged.

(I have an OBD2 code reader/data viewer (and Actron unit) that I use just to confirm the readiness monitors are all set to complete before I take my car in for smog. The smog shop tech also checks this with his own device -- at no charge -- before he hooks up the car for if he connects the car to the officlal computer and it finds any readiness monitors not complete this is a fail and I have to pay to have the car retested.)

Do not clear any codes even if none are active as this resets all readiness monitors to incomplete.

If you drive the car in a reasonable fashion and the readiness monitors are still not all complete this suggests a problem that the DME has not yet deemed worthy of an error code but could result in one shortly.

 

Thanks for the suggestion. The local auto store had a single OBDII reader for $80 so I bought a less expensive one from Amazon - https://www.amazon.com/gp/product/B005NLQAHS/ - It gets here tomorrow so I'll let it tell me when I can go back to finish the California SMOG test.

What a pain!!!

 

Well, this isn't going as planned - I've probably driven 100 miles since the battery swap - 50 freeway and 50 city - And now, with the new OBDII reader, I can see the reading:

Catalyst - Incomplete

I'll probably get another 40 miles or so today, but I don't like where this is heading. Any thoughts before I call the dealer and find out how much Catalytic Converters run?

 

That is the incomplete readiness that the scan tool will show...there is most likely nothing wrong with your cats....I asked if you have a check engine light and I am betting you don't....you need a tech that is familiar with the problem...a good tech can take their PIWIS tool and determine what driving is necessary to obtain a readiness reset...I am concerned that your dealer doesn't even know what that is....I guarantee you will have to be very lucky to obtain this yourself...I got up a 5am a couple of times and drove over 300 miles and still did not have a catalyst reset...it has to be done at different speeds for different lengths of time, with a cold start and I believe all under 3000 rpm....very difficult to do without a PIWIS tool to guide you...like I said, have your service manager call the Porsche Fresno service manager, Daniel Buono (559-860-4000) and request that he have his Porsche master tech, Jeff, talk to your dealers Porsche master tech and give him the proper procedure...it will only take them a short while to get a readiness and you will be off to the smog shop and you will pass with flying colors...another hint...make sure to drive your car for a while so it is nice and warm before you go to smog it...good luck...I was without registration for three months due to this battery change issue and my dealer not giving me the right tech when I first brought it in.

 

Your monitors have not performed the self test .You have to drive the car in a particular way .Fuel tank at least half full ,the procedure varies with each make and model.The basics are 50-55 mph for approx three miles,stop and go 0-35 mph .What this does is allows the ecu to perform self tests while driving to verify emissions system operation.Some cars take hundreds of miles of driving and some only take 2-4 miles of driving to get these monitors to pass.And the vehicle has to be at normal operating temperatures,I did smog test and repairs in calif for over thirty years and to get some vehicles to complete the monitor test was ridiculous .Each time a system repair was done and codes cleared ,or battery voltage drops below 8-9 volts, the drive cycle had to be done as well.

 

Not sure what's going on.

FWIW, both my 2002 Boxster and my 2003 Turbo manage to set all the readiness codes to complete (this after a clear codes operation) in at least a 30 mile drive from home to the office. This is a mix of a cold start, some idle time, then a short drive on city streets to the freeway and then freeway almost all the way to the office with the last 1 to 2 miles back on city streets.

I don't use full throttle but I'm sure the RPMs get above 3K and in the case of both cars remain there for a while, minutes at a stretch.

The readiness monitors probably get set to complete before that drive is over with but I don't recall ever bothering to check.

I can't believe the "drive cycle" for your 2004 differs all that much from my 2003 Turbo and my 2002 Boxster. Only very rarely does someone post about having any difficulty getting the readiness monitors to set to complete. I would think if the drive cycle was too complicated this would be a more frequent source of posts.

With that device you have, can you check for any pending codes?

Had to offer a guess I'd have to say the converters are suspect but I wouldn't buy new or even used converters based on my guess.

All I can offer is you have to do a reasonable drive cycle. I don't think it can be all city streets or all freeway. I know it can't involve WOT acceleration blasts. Under this scenario the DME goes back to open loop mode and stops monitoring the #2 O2 sensors. My guess (another one) is if this happens this resets at least the converter readiness test back to its starting point. The converter tests take some time as the DME wants to monitor the oxygen level going into the converters and the oxygen levels coming out. This is to verify the converters can store oxygen when there is an excess in the exhaust gases as it is with this oxygen that the converter catalysts metals work their "magic" on the exhaust gases.

You can consult with a Porsche tech to see if he can advise you what's required regarding the drive cycle. Obviously you want to give the DME every chance to flag the converter readiness monitor test to complete so you can smog the vehicle.

 

There is 99% chance there is absolutely nothing wrong with your cat converters...this is a problem with late model 996 ecu's and the readiness reset procedure...I don't know why people want you to chase your tail when they have never had the problem themselves or had to resolve it...as stated above getting the readiness reset can be easy or a real pain in the ****....if your reset is as difficult as mine was you will never achieve the reset on your own...pay your registration on time to avoid penalties...you will receive your tags when you pass smog...why don't you invest in a phone call to your dealer service manager or another dealer in your area and ask them about readiness reset...they should all be familiar with the problem because every late model 996 with obd2 is a candidate if there was a battery change

 

It is not having the OP chase his tail to try to use a reasonable drive cycle to try to get the readiness monitors set.

If the OP takes the car to a dealer likely he'll be charged for an hour's labor if the readiness monitors can be forced to complete. Or asked to leave the car so the tech can drive it and get the readiness monitors set. (My info is this happens more often than one might think.)

Even if the readiness monitors can be forced to complete by using the Porsche diagnostics computer one hopes they remain complete until the OP is able to get the car smog tested.

If a reasonable drive cycle is followed and the readiness monitors aren't set, at least the converter readiness monitors, this does suggest the DME is having a problem with the converters.

This makes sense since the converters are covered by an emissions warranty and the DME is going to be very deliberate before it flags a converter bad. Porsche doesn't want to replace $1200+ converters if it doesn't have to.

But after a reasonable drive cycle and no success getting the readiness monitors set to complete, and absent a hard error pointing to a bad converter, or actually even with a hard error pointing to a converter, I'd certainly talk to a Porsche tech to see what he has to offer were I in the OP's situation.

 

Yeah, I'm over 200 miles of fast and slow driving with ZERO change - "Catalyst" is still "Incomplete"

I happened to stop by a neighborhood "American car" SMOG station and while they don't service Porsche's, the guy did look through his manual for Porsche instructions (attached). Take a look at that document - I'm surprised at the number of steps to reset readiness monitors. And compare that document to my initial instructions to just "drive 25 miles at 50-55MPH."

I'm very tired of paying Porsche's rates, but it looks like I'm heading back to the dealership for this one ...

 

Readiness reset can be very stubborn as you are finding out and as I had the bad luck to find out...believe me, I totally lost faith in my dealer when they didn't have the tech I wanted do the work...I then spent three months driving with expired tags trying to get a reset...I would have never suggested you work with the dealer if I thought there was another way...but...before you spend a penny with them talk to the service manager and make sure they are aware of the problem and how to fix it...if not, take it to a dealer that can

 

Where in NorCal? I have access to a PIWIS.

 

Cameron Park - About 30 miles east of Sacto on US50 ...

But I would have no clue how to use a PIWIS. Are you offering to help?

 

Kinda far but I did stay in a Holiday Inn last night.
Yeah offering to help if you need it. I'm in the east bay. Send me a PM