993_Pilot

Help, I just failed my emissions test! I am a bit foggy on these cycles, so forgive my ignorance and paraphrasing, but are these the 6 cycle flags? I am not sure about step #2, what is PST2?

EDIT: disregard my question. . . I have a '95, therefore OBD1, so this doesn't apply to me. They used a sniffer on mine.

Only1Buck

I have used the following from RennSportSystems and has worked just fine...

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

_____________

Lorenfb

"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"

I've setup many 993s readiness codes, i.e. completed all of them and many
of those 993s in 30-45 minutes, with all three of the above conditions being
true. Also, none of the Porsche OBDII manuals which describe the readiness
codes and the driving conditions never mention the above ("discontinued").
As matter of fact, to set the CAT efficiency readiness code, a fast drive on the
freeway may facilitate completion of the test, i.e. to fully heat up the CATs.

Check here for more info:

www.systemsc.com/codes.htm

Slow Guy

I used ecobb's routine twice and it worked for me both times, no problems. I've used it on someone else's car (not Robert's) and it worked too.

As for the "idle in gear" part, I think that's for auto trans cars and not M/T cars, I just left it in neutral with clutch out. If you think about it, on a M/T car there is no diff to the engine when in gear like there is on a auto trans car.

Robert Collins - 96 993TT

I am going for a drive tomorrow to see if it works. I am thinking about getting an OBDII reader. Bill, did you ever get a reader besides the computer program you had? I cannot remember if that thing worked when you came over or not... Any suggestions on one to get? I want to get one that will show codes set as I drive so I know when they are set. Is there one that does that?

993_Pilot

As a follow-up to my earlier post, a friend of mine (a BMW nut) suggested that I try a product by CRC called G2P (Garanteed to Pass), and then give it an "Italian Tuneup", since my car had been sitting for a while. I am not sure which caused the desired improvement, but I re-tested this afternoon and Passed !!!

Slow Guy

Yes, remember I had 2, the computer program (that was a bitch to work with) and the hand held that read them fine. I had them both with me that afternoon. I'll check in my toolbox later today which one it is but I think there are ones recommended here that are a little better, not much more expensive.

I'll have to replace the computer program anyway because it won't work with the Cayenne....more tools.

plima007

Hi, I have a 1996 993 and tried the BMW routine... well, I did 2 trips and nothing. Just add miles to the speedometer, nothing else.
The ODBII does not go by speed but by RPMs. That's way the BMW routine does not always work.

After reading "The Essential Companion", Adrian Streather, (great book by the way), I follow his routine. I drove about about 30 miles and got all readiness flags green at the end!!

Here it goes the right routine. Start with the engine cold.

1. Idle (Park for Automatic Transmission or Neutral for manual T ) for 10-15 min
2. Drive 8 miles @2200 RPMs
3. Drive 5 miles @2500 RPMs
4. Drive 8 miles @1800 RPMs
5. Idle (Park) for 3 min.

- You cannot turn off the engine between steps.
- You can slow down in each step (for stop signs or traffic, etc). If so, just extend a bit more the miles. The most important is that you have a constant period of time at right regime. The routine already includes plenty of margin.
- Never exceed 2800 RPMs.
- In my case I just took a rural 6 mile road with not much traffic and travel back and forward. On the 8 miles step, I had to stop to turn around. No problem with that, just extend the leg to 10 miles.

Tomorrow I'll do the State Inspection!!
Give it a try folks!

plima007

updated previous post.

bobbyd

I get my dealer to do it. Cost s me about $200 and they give me a Porsche loaner. Lasts about 2 years before Check engine light returns. Repeat. Easy and no sweat. Plus nobody touches my engine, which runs perfect.

golfnutintib

yes this is what is known as the BMW cycle... I have found it does not always work in P Cars...

rpaitich

Thanks for the post Plima; this method looks a lot easier to implement. I have Streather's 993 book and find it helpful. I can't find this procedure in my 2005 edition. Please point me to the page so that I can mark it for future ref..
Thanks,
Ron

Lorenfb

Some '96 vehicles require three trips, i.e. three cold starts.

desmo33

This procedure was news to me! It is found on page 192 of the Streather book.

I just successfully got all monitors to set after 2 "trips" using this procedure, with an overnight cool-down in between. Much more flexible than my past attempts at the BMW procedure. I found a pretty open ~2 mile stretch of road with few traffic lights and just kept u-turning until the required distances had been covered (Westchester Parkway on the north side of LAX for anyone in the area). I never exceeded ~45 mph. My car is a 1997 C2 with a build date of 11/96.

gmorat

Good to go? I remember the trouble I had with my first 96 C2 Couple. Readiness codes were never set on that car.