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993 Fail CA Smog: Failure to complete all OBD self tests
I have been reading some of your post and even brought my car to the CA State Referee but still could not get my car to pass smog. Bought the car online from Florida, and I'm now trying to register it here in CA. It's a 1996 993 C2 with 36k miles and pretty much stock with a tuned exhaust.
Help?
Seeing the low miles, I would just replace the inexpensive air injector check valve as it is subject to internal corrosion failure and drive the car until all the readiness switches (flags) trip to yes. The previous owner probably let the battery run down, replaced it and in the process caused the readiness flags to reset.
There are many postings here on Rennlist on how to replace the check valve and the elements of the drive to set readiness.
My posting on how to remove the check valve is the one to use if the less aggressive alternatives don't work: https://rennlist.com/forums/993-foru...e-basterd.html
Andy
'96 993's can be more difficult to set all of the Readiness Monitors due to how tightly Porsche set the limits for each parameter so patience is required. Remember, these were the first OBD-2 vehicles,.......
'97 and later cars received modified software at the factory to make this process a little easier to do.
Back when we had a referee, it was easy to go in and have the sniffer test done. When they stopped that program, I used to work on drive cycles until I was blue in the face. One time I gave in and took to S-Car-Go and by some miracle, it passed every time since then. Don't ask, don't tell...
Seeing the low miles, I would just replace the inexpensive air injector check valve as it is subject to internal corrosion failure and drive the car until all the readiness switches (flags) trip to yes. The previous owner probably let the battery run down, replaced it and in the process caused the readiness flags to reset.
There are many postings here on Rennlist on how to replace the check valve and the elements of the drive to set readiness.
My posting on how to remove the check valve is the one to use if the less aggressive alternatives don't work: https://rennlist.com/forums/993-foru...e-basterd.html
Andy
Back when we had a referee, it was easy to go in and have the sniffer test done. When they stopped that program, I used to work on drive cycles until I was blue in the face. One time I gave in and took to S-Car-Go and by some miracle, it passed every time since then. Don't ask, don't tell...
My friend just said the same thing today. I'll try that too.
No, the car drives fine. I believe the car battery was disconnected for a long time.
Not 100% clear from the report what the issue is but if the CEL was off, its probably just a readiness issue i.e. your car hasn't driven enough to fully run all its tests (monitors) since the battery was reconnected. Get a cheap ODB scanner and do some driving. You'll be able to tell when the car is ready, saving a repeat of what you just went through. It'll also tell you if any of the tests failed, and what the fault codes were. Well worth the money IMO.
I agree with Steve - 96's are much harder to set the monitor. I can do my 97 about 45 minutes.
Good luck.
I always run a cheap obd scanner on my car to make sure all the readiness codes are set before I get a smog. Usually, if you fail once that garage will give you a discount to run it again when you think it should pass.
Also when I first got my car, not knowing anything about the readiness codes, etc., and it failed. I just asked a mechanic to get it smogged for me with the paperwork. At the same time had the car looked over.
^^^ Excellent point. A scanner will help avoid this.
Readiness aside...In some states, if you FAIL on an initial test (CEL lit), the associated monitor has to be ready on retest. This is to prevent someone from intentionally masking the same fault on retest by simply resetting the system and doing a drive that prevents the associated monitor from running to completion (ask me how I know ). Not many states have this rule, so check with your local DMV to avoid another black mark on your carfax.
Jay777 and jcochran1, first of all I want to thank you for all your work on this topic. Your contribution on Rennlist is invaluable. I have been busy reading your other post and actually forgot to check my own.
I just bought this 1996 993 C2 shipped from Florida sight unseen, and it failed the readiness thing all 5. No CEL lit. So yes I have to drive the car. I looked everywhere for an Altel AL519 but only found them on Amazon, so have to wait till Tuesday for it.
I'm going to do the sequence Jay recommended, which is the 5/30/2016 version and cross my fingers. Hopefully by Tuesday night my car will be "ready".
Please let me know if you have other recommendations.
10-27-2018, 10:05 AM
993 Fail CA Smog: Failure to complete all OBD self tests
). Not many states have this rule, so check with your local DMV to avoid another black mark on your carfax.
