coltj

Success!!!! It worked!!! Well we were finally to reset the readiness codes on my friend’s ’96 TT using the procedure that Steve Weiner posted some time ago.

Background: Friend bought a low-mileage(12K) ’96 TT about 5 months ago(I purchased his ’96 C4). Car would not pass Mass. State emissions test because the readiness codes were not “ready”. Even after driving the car ~2K during the 4 months after the failure none of the non-continuously monitored codes had reset.

So we decided to give “Steve’s procedure” a try. As we did not have access to a dyno or to a track, we left the car at a rest stop along the Mass Pike for about 13 hours last Saturday. Then we headed west.

Immediately after completing the cycle, we checked the codes and were disappointed to say the least that NONE of the codes had reset. But wait!!! After 5 minutes of additional driving, one code reset. 10 minutes later a second reset. Checked the codes the following morning, after an additional 30 miles of driving, and 2 more were ready. Only the O2 sensor code was “unready”. Checked the car 2 days ago(after 120 miles more driving) and all codes were ready. Car passed inspection today. Jungle Dave is very happy!!

All in all, the procedure was not that difficult to execute with 2 people, a good driver and a copilot(me) to monitor times etc.

Many thanks to Steve W for his advice. Yes, this forum is a great place.

Mike A.

I have read this thread and others on this topic with interest since I am now having the same problem with my '97 993S ,i.e. Readiness codes not restting.
Can someone repost the protocal for resetting the codes, please.
TIA

coltj

Here's the procedure(thanks to Steve W. from Rennsport I believe)

OBD-II Readiness Driving Cycle
One of the most common problems with OBD-II cars ('96-0n) are smog test failures due to readiness codes not set and the ECU will test as "Not Ready".
Here are some procedures for setting all 9 readiness codes in OBD-II ECU's. These "Diagnostic Trip" steps MUST be followed to the letter otherwise you will have to start all over again. Review these carefully so you can see what you will be doing before you begin.
1) Start cold engine and idle for approximately 2 minutes, 10 seconds. This checks secondary air injection and evaporative leak detection systems.
2) Accelerate to 20-30 MPH and maintain steady speed for 3 minutes, 15 seconds. This establishes closed loop oxy-sensor operations, response times & switching times.
3) Accelerate to 40-60 MPH and maintain steady speed for 15-20 minutes. This evaluates catalytic converters while oxy-sensor response and switching times are checked.
4) De-accelerate and come to a stop. Idle in gear for 5-6 minutes. This checks evaporative leak detection system.
Remember:
The diagnostic checks above will be discontinued if:
1) Engine speeds exceed 3000 RPM
2) Large fluctuations in throttle position
3) Road speeds exceed 60 MPH

Mike A.

coltj
Thank you. I will try this today.

hddude

How in the world did you guys who have used this procedure follow it to the letter? It seems like I'd have to leave my car overnight at a track in order to start and idle it cold, then proceed through the precise steps. How'd you do it?!

I tried to do it within the limitations of where I keep my car in Phoenix and of course couldn't follow the directions to the tee...and it predictably didn't work.

Steve, or anyone else, do you have any suggestions for those of us who don't have a track in our backyards? The stealer in Scottsdale offered to provide the service for $360!!! That would make the total cost of my new battery nearly $500. For kerrrrist sakes...ain't this a wonderful country?

I live in AZ and don't think I can get a waiver via a "referee" like CA seems to have. It's crazy to think a mere battery change causes this much grief.

993inNC

Just get in the car and drive steady for at least 100 miles of uninterupted steady speed of 80+/-. I have done it twice in my car and each time all codes reset (total round trip was 300 miles)

hddude

Thanks for the suggestion. Not that I mind at all driving my Porsche for 300+ miles, but is this really the only "easy" way to solve this crazy issue? I'd be curious if others have any other solutions.

coltj

hddude, you have a PM.

mkc4s

On my 1997 C4S, it didn't take that much effort to get codes ready for inspection. I had the battery disconnected for over two weeks until around September 5th. I drove the car four times in September and October, about 25-30 miles each time. On November 4th, I went for inspection (which includes reading of computer codes) and passed.

993inNC

You may not have to do 300 miles, its just been the distance I WAS driving anyway, it may have happened sooner, but it has worked both times without trying. I tried all the other ways and it throws my SAI code. Its worth a try for you.

g_murray

I have a question...

Number 4 -- ...idle "in gear" for 5-6 minutes. For those of us with manny-trannys - am I supposed to be 'in gear' (say 4th.) and holding my foot on the clutch for 6 mins. with the handbrake on and at a dead stop? Seems a bit weird to me. (How does the OBD know if you're in gear ...or not? ...or with your foot in/out of the clutch? )

Ger.

TCallas

I have a factory 993 OBD II manual that explains the process necessary to complete these monitors and this process needs to be completed twice to obtain one trip which will complete all of your monitors but you should be using the PST-2 (Porsche systems tester-2) for this. Otherwise, I highly recommend using Steve Weiner's list. It will make your life much easier.

Slow Guy

Shortly after getting my car I had problems getting my car to pass the TN OBDII test (since the battery had been replaced). After multiple attempts using normal driving it still had not set the readiness indicators. I looked for and found 2 procedures, one much like the one from Steve W. and one from BMW. I took a Sat/Sun. morning and performed both, then Mon. morning went and retested and passed with no problems.

I figured out what I was doing wrong, I had been trying to keep the RPM's ABOVE 4k as much as possible when both procedures instructed to stay BELOW 3k at all times during runs. Also, I had taken the car above 70 mph when both procedures said to stay below 60 - 65mph.

So, my suggestion, follow Steve's procedure and stay below 3k RPM and 60 mph.

It took about 1 hr. seat time for each procedure but was better than a 300 - 500 mi. drive.

coltj

Number 4 -- ...idle "in gear" for 5-6 minutes. For those of us with manny-trannys - am I supposed to be 'in gear' (say 4th.) and holding my foot on the clutch for 6 mins. with the handbrake on and at a dead stop? Seems a bit weird to me. (How does the OBD know if you're in gear ...or not? ...or with your foot in/out of the clutch

My answer is yes, in gear, clutch in(obviously) for manual trans. At least that's what I did the one time I did the sequence with success.

hddude

Were you able to follow each step of the procedure precisely, and if not, did it matter? One poster PM'd me and said he left his car for a few hours near a freeway ramp to ensure he could start the car cold and do each step precisely. I hope I can avoid doing that or else I may have a stolen car problem to add to my readiness code problem.