The official PORSCHE 993 OBD II test drive
08-12-2009, 11:37 AM
#16
"Can these cycles be done independently of each other, so if you miss one on one day can you come back and re-try or do you start all over again with all of them?"
No! One must complete one drive cycle (trip) before the engine is shut-off or one must re-begin the
complete drive cycle at the next start-up. The chart shown indicates what must be done before
a drive cycle (trip) is completed and when the engine can be shut-off and restarted to begin the
next drive cycle. A minimum of two drive cycles are required, in some cases (early '96) three
drive cycles may be required. Once the required number of drive cycles are completed,
the OBDII readiness codes (monitors) will be indicated (viewable) via an OBDII scanner.
Read here (Porsche 993 Cycle Flag Basics) for more info; www.systemsc.com/codes.htm
No! One must complete one drive cycle (trip) before the engine is shut-off or one must re-begin the
complete drive cycle at the next start-up. The chart shown indicates what must be done before
a drive cycle (trip) is completed and when the engine can be shut-off and restarted to begin the
next drive cycle. A minimum of two drive cycles are required, in some cases (early '96) three
drive cycles may be required. Once the required number of drive cycles are completed,
the OBDII readiness codes (monitors) will be indicated (viewable) via an OBDII scanner.
Read here (Porsche 993 Cycle Flag Basics) for more info; www.systemsc.com/codes.htm
08-12-2009, 04:34 PM
#17
R.I.P
Rennlist Member
Rennlist Member
Thread Starter
1. In order to do this you have to have an OBD II reader to see what progress you have made.
2. Porsche has a tool that lets them see which flags have reset (your OBD II reader will also tell you that) and it also tells them what load the engine is experiencing . The OBD II reader won't tell you that.
3. From past experience I can tell you that the flags reset under a light engine load (easy on the throttle). You need at least 2 engine cycles for the secondary air injection.
4. Some flags won't reset until others have reset (adaption range 2 has to reset before adaption range 1).
5. You do not have to do this all during the same drive. Once a flag has reset, it will stay reset until you have a fault with that function or perform an OBD II reset (by disconnecting the battery or using the OBD II reader).
6. The drive has to be at least 1000 seconds (~16 minutes).
7. Two of the flags reset at idle.
If you look at the BMW procedure you can see where you are meeting these conditions. If you use it just use light throttle inputs when accelerating. I have been resetting mine every year for PA emissions inspection. My car will throw a CEL (SAI, p1411) every 1500 miles or so after I reset everything. When I am in rural VA I have roads where I can drive at 2000 rpm for 20 minutes without stopping and it does the trick. If I need to do it in Philly, it is easiest to do early in the AM (4AM - 5 AM) when there are no cars on the road. If there is a lot of traffic there is too much stop and go.
Good luck
2. Porsche has a tool that lets them see which flags have reset (your OBD II reader will also tell you that) and it also tells them what load the engine is experiencing . The OBD II reader won't tell you that.
3. From past experience I can tell you that the flags reset under a light engine load (easy on the throttle). You need at least 2 engine cycles for the secondary air injection.
4. Some flags won't reset until others have reset (adaption range 2 has to reset before adaption range 1).
5. You do not have to do this all during the same drive. Once a flag has reset, it will stay reset until you have a fault with that function or perform an OBD II reset (by disconnecting the battery or using the OBD II reader).
6. The drive has to be at least 1000 seconds (~16 minutes).
7. Two of the flags reset at idle.
If you look at the BMW procedure you can see where you are meeting these conditions. If you use it just use light throttle inputs when accelerating. I have been resetting mine every year for PA emissions inspection. My car will throw a CEL (SAI, p1411) every 1500 miles or so after I reset everything. When I am in rural VA I have roads where I can drive at 2000 rpm for 20 minutes without stopping and it does the trick. If I need to do it in Philly, it is easiest to do early in the AM (4AM - 5 AM) when there are no cars on the road. If there is a lot of traffic there is too much stop and go.
Good luck
08-12-2009, 09:47 PM
#18
"1. In order to do this you have to have an OBD II reader to see what progress you have made."
Actually, that's incorrect as an OBDII reader won't provide ANY info until ALL
drive cycles (trips) are complete.
"2. Porsche has a tool that lets them see which flags have reset (your OBD II reader will also tell you that) and it also tells them what load the engine is experiencing . The OBD II reader won't tell you that."
Again incorrect, as the OBDII reader provides NO info as per the previous
comment. Also, the flags get SET as the tests are completed and get RESET
with a DTC reset, a battery disconnect or engine shutoff. The term RESET
whether a PC or the OBDII monitoring system always denotes the default
state which is no monitors complete for the OBDII system. And for a PC,
a RESET places a PC in its initial state before the problem, e.g. "blue screen"
lockup. You SET your digital watch to the correct time and RESET your stop
watch to it default state of zero elapsed time.
"3. From past experience I can tell you that the flags reset under a light engine load (easy on the throttle). You need at least 2 engine cycles for the secondary air injection."
Again incorrect, the SAI gets done at a cold engine start, once per drive cycle.
Read the posted document.
"4. Some flags won't reset until others have reset (adaption range 2 has to reset before adaption range 1)."
Yes there's a sequence and if one test fails the others won't be performed,
e.g. SAI & Tank Venting must complete first.
"5. You do not have to do this all during the same drive. Once a flag has reset, it will stay reset until you have a fault with that function or perform an OBD II reset (by disconnecting the battery or using the OBD II reader)."
Again wrong, as all tests within a drive cycle must complete before engine
shut-off or all the tests start from the beginning at the next engine startup.
Bottom Line: Please don't provide misleading info for 993 owners, i.e. confuse
other vehicle's operation or fail to properly present the 993 OBDII monitoring system.
For many, setting all the OBDII monitors are annoying enough without being
misled on the process.
Actually, that's incorrect as an OBDII reader won't provide ANY info until ALL
drive cycles (trips) are complete.
"2. Porsche has a tool that lets them see which flags have reset (your OBD II reader will also tell you that) and it also tells them what load the engine is experiencing . The OBD II reader won't tell you that."
Again incorrect, as the OBDII reader provides NO info as per the previous
comment. Also, the flags get SET as the tests are completed and get RESET
with a DTC reset, a battery disconnect or engine shutoff. The term RESET
whether a PC or the OBDII monitoring system always denotes the default
state which is no monitors complete for the OBDII system. And for a PC,
a RESET places a PC in its initial state before the problem, e.g. "blue screen"
lockup. You SET your digital watch to the correct time and RESET your stop
watch to it default state of zero elapsed time.
"3. From past experience I can tell you that the flags reset under a light engine load (easy on the throttle). You need at least 2 engine cycles for the secondary air injection."
Again incorrect, the SAI gets done at a cold engine start, once per drive cycle.
Read the posted document.
"4. Some flags won't reset until others have reset (adaption range 2 has to reset before adaption range 1)."
Yes there's a sequence and if one test fails the others won't be performed,
e.g. SAI & Tank Venting must complete first.
"5. You do not have to do this all during the same drive. Once a flag has reset, it will stay reset until you have a fault with that function or perform an OBD II reset (by disconnecting the battery or using the OBD II reader)."
Again wrong, as all tests within a drive cycle must complete before engine
shut-off or all the tests start from the beginning at the next engine startup.
Bottom Line: Please don't provide misleading info for 993 owners, i.e. confuse
other vehicle's operation or fail to properly present the 993 OBDII monitoring system.
For many, setting all the OBDII monitors are annoying enough without being
misled on the process.
Last edited by Lorenfb; 08-12-2009 at 10:10 PM.
08-13-2009, 12:10 AM
#21
"My Durametric will let you see what is set & what is not. You get a pass/fail thing for each one."
My older version of the Durametric reads the same readiness info as most
generic OBDII scanners. A few years ago I suggested that it also indicate
the flag status which may now be integral, but I doubt it. If this were the
case, it would be very usual for 993 owners in setting all the readiness
states, i.e. indicating which readiness states, e.g. secondary injection,
were problematic.
My older version of the Durametric reads the same readiness info as most
generic OBDII scanners. A few years ago I suggested that it also indicate
the flag status which may now be integral, but I doubt it. If this were the
case, it would be very usual for 993 owners in setting all the readiness
states, i.e. indicating which readiness states, e.g. secondary injection,
were problematic.
08-13-2009, 08:03 PM
#22
Nordschleife Master
"My Durametric will let you see what is set & what is not. You get a pass/fail thing for each one."
My older version of the Durametric reads the same readiness info as most
generic OBDII scanners. A few years ago I suggested that it also indicate
the flag status which may now be integral, but I doubt it. If this were the
case, it would be very usual for 993 owners in setting all the readiness
states, i.e. indicating which readiness states, e.g. secondary injection,
were problematic.
My older version of the Durametric reads the same readiness info as most
generic OBDII scanners. A few years ago I suggested that it also indicate
the flag status which may now be integral, but I doubt it. If this were the
case, it would be very usual for 993 owners in setting all the readiness
states, i.e. indicating which readiness states, e.g. secondary injection,
were problematic.
I'll try to get a screen shot of it. You can see each flag & either a green pass, or a red fail for each one.
It's useful to see what ones are not set yet. In almost 6months of driving, I still have a couple of codes that are not set!
Why don't you download the the latest software?
08-14-2009, 12:40 AM
#23
"I'll try to get a screen shot of it. You can see each flag & either a green pass, or a red fail for each one."
Are they the "flags" as uniquely provided by the Porsche only testers or
are they the actual OBDII readiness status provided by most scanners,
i.e. the continuous & the non-continuous tests? I guess maybe a call to
Durametrics to determine if that feature is in the works.
Are they the "flags" as uniquely provided by the Porsche only testers or
are they the actual OBDII readiness status provided by most scanners,
i.e. the continuous & the non-continuous tests? I guess maybe a call to
Durametrics to determine if that feature is in the works.
08-18-2009, 01:29 PM
#24
Spoke to Durametrics and they indicated that in 6 - 8 wks their software will allow access
to the cycle flags to facilitate an OBDII emission's test setup of the readiness states (monitors).
Presently the software lacks this feature.
to the cycle flags to facilitate an OBDII emission's test setup of the readiness states (monitors).
Presently the software lacks this feature.
08-18-2009, 10:05 PM
#25
"I'll try to get a screen shot of it. You can see each flag & either a green pass, or a red fail for each one."
Are they the "flags" as uniquely provided by the Porsche only testers or
are they the actual OBDII readiness status provided by most scanners,
i.e. the continuous & the non-continuous tests? I guess maybe a call to
Durametrics to determine if that feature is in the works.
Are they the "flags" as uniquely provided by the Porsche only testers or
are they the actual OBDII readiness status provided by most scanners,
i.e. the continuous & the non-continuous tests? I guess maybe a call to
Durametrics to determine if that feature is in the works.
It's obvious you have a WAY better understanding of this topic than probably 99.99% of us. So I'll ask what myself and others may be thinking.
Why is important to know the flag status? Aren't the readiness codes ultimately what are needed in
order to get the inspection performed?
After reading the responses to my recent thread "Can't pass NYS emissions", I went out and bought the Actron 9180. It let me know that most items were 'inc', 2 items were 'N/A' and none were 'OK. I ran through the "BMW drive cycle" and the following morning before going to repeat the cycle, I decided to run the scanner again. To my pleasant surprise all the 'inc' items were now 'OK.' So no need to repeat the drive cycle. Anyway, the point is that why do I even care what the flag status is, as long as I get the readiness codes to read 'OK'?
08-18-2009, 11:16 PM
#26
"Why is important to know the flag status?"
To determine the progress of the whole process and what may be problematic, e.g. the SAI test.
With the 993 OBDII system, none of the readiness states are indicated until the complete
testing process is finished. That complicates the driving, as one never really knows what
maybe "hanging" the completion process.
"Aren't the readiness codes ultimately what are needed in
order to get the inspection performed?"
That's correct, but for many the readiness codes don't always set easily
as many will confirm, and one needs to determine the issue/issues
which the flag status provides.
"Anyway, the point is that why do I even care what the flag status is, as long as I get the readiness codes to read 'OK'?"
Again, you are one of the more fortunate ones where the readiness codes
set with minimal driving efforts, i.e. your engine & emission system are
basically optimum.
To determine the progress of the whole process and what may be problematic, e.g. the SAI test.
With the 993 OBDII system, none of the readiness states are indicated until the complete
testing process is finished. That complicates the driving, as one never really knows what
maybe "hanging" the completion process.
"Aren't the readiness codes ultimately what are needed in
order to get the inspection performed?"
That's correct, but for many the readiness codes don't always set easily
as many will confirm, and one needs to determine the issue/issues
which the flag status provides.
"Anyway, the point is that why do I even care what the flag status is, as long as I get the readiness codes to read 'OK'?"
Again, you are one of the more fortunate ones where the readiness codes
set with minimal driving efforts, i.e. your engine & emission system are
basically optimum.
08-20-2009, 09:05 AM
#27
"Why is important to know the flag status?"
To determine the progress of the whole process and what may be problematic, e.g. the SAI test.
With the 993 OBDII system, none of the readiness states are indicated until the complete
testing process is finished. That complicates the driving, as one never really knows what
maybe "hanging" the completion process.
"Aren't the readiness codes ultimately what are needed in
order to get the inspection performed?"
That's correct, but for many the readiness codes don't always set easily
as many will confirm, and one needs to determine the issue/issues
which the flag status provides.
"Anyway, the point is that why do I even care what the flag status is, as long as I get the readiness codes to read 'OK'?"
Again, you are one of the more fortunate ones where the readiness codes
set with minimal driving efforts, i.e. your engine & emission system are
basically optimum.
To determine the progress of the whole process and what may be problematic, e.g. the SAI test.
With the 993 OBDII system, none of the readiness states are indicated until the complete
testing process is finished. That complicates the driving, as one never really knows what
maybe "hanging" the completion process.
"Aren't the readiness codes ultimately what are needed in
order to get the inspection performed?"
That's correct, but for many the readiness codes don't always set easily
as many will confirm, and one needs to determine the issue/issues
which the flag status provides.
"Anyway, the point is that why do I even care what the flag status is, as long as I get the readiness codes to read 'OK'?"
Again, you are one of the more fortunate ones where the readiness codes
set with minimal driving efforts, i.e. your engine & emission system are
basically optimum.
Good day.
08-22-2009, 10:45 PM
#28
Race Director
I started another thread with this but I think it might be beneficial here too.
========
About 4 mos ago I disconnected the battery on my ’97 993 for some routine maint. and other work. After reconnecting the battery I decided I wanted to try an un-scientific test of the OBDII Readiness Flags. I decided I would drive the 993 as I normally would for a few months until just before it was time for me to renew the registration which in TN requires an annual emissions test (no sniffer, just pass the OBDII tests). Since in the past I’ve never had any problems using the so called “BMW OBD ii Drive Cycles Procedure” to get my readiness indicators to set I wasn’t too worried about having any issues.
The Code Reader I use is the INNOVA 3100 and I’ve had it for several years, I think I paid less than $100 for it. The only time I’ve had a problem with it was caused by operator error (me) when I failed to disable the Immobilizer and the reader couldn’t communicate with the car. I learned that lesson the hard way.
I don’t know how many miles I put on before I hooked up the tester to check (remember I said un-scientific) but it had to have been in excess of 1500 mi. I drove the 993 as I normally would which includes regular excursions above 5k+ RPM. I did not try to baby the car for the sake of this test.
When I hooked up the OBDII Reader today I was not surprised that only following (3) Monitors (Readiness Indicators) were set:
M - Misfire
F - Fuel System
CC - Comprehensive Component
The following (5) Monitors were in a Non-set (flashing) condition:
C - Catalyst
EV - Evaporative System
2A - Sec. Air System (SAI)
O - Oxygen Sensor
OH – Oxygen Sensor Heater
There are a total of (11) Monitors but as the OBDII Reader’s Manual says “not all vehicles support all 11 monitors”. I deduce the Porsche supports only 8.
After performing the “BMW OBDII Drive Cycle Procedure” the first time on Sat. morning and returning home the status of the monitors had not changed, 3 were still set and 5 were flashing (not set). It should be noted that I left the OBDII Reader connected to the OBDII port the entire time while I was driving, once a minute or so the Reader would “refresh” (ping the 993”s OBDII system) itself. At no time did any of the Readiness Indicators change their status during or after the first run.
After letting the 993 sit (cool) for about 4 hrs. I decided to try the second run (in the past I let the car sit overnight, not this time). I went on a slightly different route but it still allowed me to run the “BMW OBDII Drive Cycle Procedure” in order. All through the drive the Reader was still connected to the car and there was no change to the 3 set/5 flashing status until I got home. I backed into the driveway and pulled the handbrake to complete the final step which is “Idle for apx. 5 min.” (in-gear for auto transmission cars only). After less than 1 ˝ min. of idling the 5 remaining Readiness Indicators set (all on solid, none flashing)! Success! In the words of Jackie Gleason “How sweet it is!”
To be clear I was rarely able to complete any individual step of the “BMW OBDII Drive Cycle Procedure” without a break for a stop sign or to go around a corner, I would just return to the speed and RPM I was moving in as soon as possible. I did however extend the drive on that step of the procedure for as long as that section of road allowed (without getting ridiculous). However it is critical that you not exceed 3K RPM or 60 MPH for the duration of the test. I did however, on 2 occasions exceed the 3K/60 MPH limit but not by much and it was for a very brief period of time so I don’t think that is a “hard and fast” rule, just try your best to avoid it.
I have photos of the Reader connected and the display that I will upload tonight.
Someone (I don’t remember who) wrote out the “BMW OBDII Drive Cycle Procedure” so we didn’t have to use the PDF file, hopefully they won’t mind if I copy it and put it in this thread. Save me some more typing.
Hope this helps.
========
About 4 mos ago I disconnected the battery on my ’97 993 for some routine maint. and other work. After reconnecting the battery I decided I wanted to try an un-scientific test of the OBDII Readiness Flags. I decided I would drive the 993 as I normally would for a few months until just before it was time for me to renew the registration which in TN requires an annual emissions test (no sniffer, just pass the OBDII tests). Since in the past I’ve never had any problems using the so called “BMW OBD ii Drive Cycles Procedure” to get my readiness indicators to set I wasn’t too worried about having any issues.
The Code Reader I use is the INNOVA 3100 and I’ve had it for several years, I think I paid less than $100 for it. The only time I’ve had a problem with it was caused by operator error (me) when I failed to disable the Immobilizer and the reader couldn’t communicate with the car. I learned that lesson the hard way.
I don’t know how many miles I put on before I hooked up the tester to check (remember I said un-scientific) but it had to have been in excess of 1500 mi. I drove the 993 as I normally would which includes regular excursions above 5k+ RPM. I did not try to baby the car for the sake of this test.
When I hooked up the OBDII Reader today I was not surprised that only following (3) Monitors (Readiness Indicators) were set:
M - Misfire
F - Fuel System
CC - Comprehensive Component
The following (5) Monitors were in a Non-set (flashing) condition:
C - Catalyst
EV - Evaporative System
2A - Sec. Air System (SAI)
O - Oxygen Sensor
OH – Oxygen Sensor Heater
There are a total of (11) Monitors but as the OBDII Reader’s Manual says “not all vehicles support all 11 monitors”. I deduce the Porsche supports only 8.
After performing the “BMW OBDII Drive Cycle Procedure” the first time on Sat. morning and returning home the status of the monitors had not changed, 3 were still set and 5 were flashing (not set). It should be noted that I left the OBDII Reader connected to the OBDII port the entire time while I was driving, once a minute or so the Reader would “refresh” (ping the 993”s OBDII system) itself. At no time did any of the Readiness Indicators change their status during or after the first run.
After letting the 993 sit (cool) for about 4 hrs. I decided to try the second run (in the past I let the car sit overnight, not this time). I went on a slightly different route but it still allowed me to run the “BMW OBDII Drive Cycle Procedure” in order. All through the drive the Reader was still connected to the car and there was no change to the 3 set/5 flashing status until I got home. I backed into the driveway and pulled the handbrake to complete the final step which is “Idle for apx. 5 min.” (in-gear for auto transmission cars only). After less than 1 ˝ min. of idling the 5 remaining Readiness Indicators set (all on solid, none flashing)! Success! In the words of Jackie Gleason “How sweet it is!”
To be clear I was rarely able to complete any individual step of the “BMW OBDII Drive Cycle Procedure” without a break for a stop sign or to go around a corner, I would just return to the speed and RPM I was moving in as soon as possible. I did however extend the drive on that step of the procedure for as long as that section of road allowed (without getting ridiculous). However it is critical that you not exceed 3K RPM or 60 MPH for the duration of the test. I did however, on 2 occasions exceed the 3K/60 MPH limit but not by much and it was for a very brief period of time so I don’t think that is a “hard and fast” rule, just try your best to avoid it.
I have photos of the Reader connected and the display that I will upload tonight.
Someone (I don’t remember who) wrote out the “BMW OBDII Drive Cycle Procedure” so we didn’t have to use the PDF file, hopefully they won’t mind if I copy it and put it in this thread. Save me some more typing.
Hope this helps.
Last edited by Slow Guy; 12-24-2014 at 01:38 PM.
08-23-2009, 12:24 PM
#29
Race Director
You cannot see that in the first photo the monitors C, EV, 2A, O and OH are flashing but they are. You'll also notice "DONE" in the second photo, this did not happen until the last 5 monitors had set.
08-23-2009, 02:28 PM
#30
"After letting the 993 sit (cool) for about 4 hrs. I decided to try the second run"
Yes, that's the procedure, i.e. two trips not necessarily a 4 hr wait between.
When all elements of the emission system are working properly, it's that easy.
"The only time I’ve had a problem with it was caused by operator error (me) when I failed to disable the Immobilizer and the reader couldn’t communicate with the car."
That's always the case even with the Porsche factory testers.
Yes, that's the procedure, i.e. two trips not necessarily a 4 hr wait between.
When all elements of the emission system are working properly, it's that easy.
"The only time I’ve had a problem with it was caused by operator error (me) when I failed to disable the Immobilizer and the reader couldn’t communicate with the car."
That's always the case even with the Porsche factory testers.
