OBD2 Catalyst Monitoring Not Ready

I needed to get my car (with new engine) inspected so it could be registered but for some reason, I couldn't get the catalyst monitoring to set to ready. I drove around for a few days and still not ready. Idled the car for a bit. Still not ready. I searched on the Internet and step 1 for OBD2 readiness is idling the car with the air conditioning and rear defroster on from cold start. Shockingly, this did it. Monitoring is ready and was able to pass inspection.

From what I've seen, doing a complete drive cycle isn't always necessary - the readiness monitor should indicate which procedures need to be carried out, which in your case did the trick. Congrats! Had you recently disconnected the battery or had some other condition that caused the car to not be emissions-test ready?

Yes, brand new motor and then had a secondary air pump issue that was just taken care of. https://itunes.apple.com/us/app/dash...321293183?mt=8 and Amazon.com: ieGeek� WIFI Wireless OBD2 Auto Scanner Adapter Scan Tool for iPhone iPad iPod: Electronics Amazon.com: ieGeek� WIFI Wireless OBD2 Auto Scanner Adapter Scan Tool for iPhone iPad iPod: Electronics has been a great cheap investment to read/erase codes and monitor the car.

You'll need to drive the car on a highway at a constant speed (around 60mph) at a steady rate (cruise control) for about 30 miles. Pick a highway that is rural during low volumes. The system needs time to see if the converters are working right and part of it is steady highway speed.

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The idling was the key. I've driven a number of times -- more often than not -- with the A/C off and with the car with a rear window defroster with this off as well and all the readiness monitors have reached completion with no real difficulty or delay. Basically, start the engine cold, let it idle a minute or two -- I use the secondary air injection pump as a "timer", when it shuts off that's my signal the engine is ready to be used -- then drive off and keep RPMs under 4K until the engine is fully up to temperature. You want a mix of driving: stop and go; some low speed (<45mph) cruising, and some high speed (>= 45mph) cruising tossed in. Avoid the temptation to engage in hard acceleration runs. Big engine loads that arise from hard acceleration cause the DME to switch to open loop mode and this suspends any monitoring of the converter function.

It's been 700 miles of mixed condition driving since I changed the spark plugs and mine was not ready when I took it into smog today. I guess I'll try the idle with AC and rear defrost tomorrow. I never idle the car to start. My mechanic told me to take off immediately upon start and keep it under 3 until the engine was warmed up...then never shift before 4.

Still not reaching ready status on Catalyst Monitoring. Thoughts? I turned on the AC and rear defrost from a cold start (after parking overnight) and let it idle until the secondary air pump shut off and the RPMs dropped. Car has ~800 miles since I unhooked the battery to change spark plugs. Mufflers were removed, ground wire was also removed during this process. While the car was up, I removed the air pump because I wanted to check the engine mounts. I also changed the air filter. I took out the box and disconnected the MAF to remove the crumbling spongy resonator stuff and housing. There are no stored or active errors. I changed brake pads last week but I don't think that should do anything - battery was not disconnected. I think that's everything. Thanks in advance for any guidance.

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What you are doing ain't working. Time to try something different. Let the engine idle a bit after a cold start. Keeping engine RPMs under 3K is a bit overkill-ish. I just keep RPMs under 4K (more like 3.5K) until the engine is fully warmed up. Once the engine is warmed up if you always go over 4K before you upshift I think that's pushing the engine too hard and is probably interfering with the readiness tests, preventing them from completing. Pretty much the above is how I drive my Boxster (and Turbo) and sometime during my commute drive of 30 miles all the readiness monitors are set to complete. This probably happens at some point before the 30 miles are up I just never bothered to monitor the readiness test progress to try to find out exactly when. That it happens and I don't have to do anything "special" is all that matters to me.

I agree. Based on some input, I'll get a scanner, mimic some of the 993 cycle procedures. I'm going to do when there's less traffic, I'm in a dense area - I rarely get to cruise uninterrupted at slower speeds...or higher speeds.

Some of us have much more difficulty with this than others and for no diagnose-able reason. There is an official Drive Cycle procedure which is often quoted(see Renntech for more) but for some that does not work until many Drive Cycle attempts have been made. Another issue is the Drive cycle for older/different models like the 993 may not be relevant because they have slightly different systems and parameters. Assuming there is not an equipment defect (major assumption on our aging cars!) , don't overlook the possibility of marginal cats/O2 sensors, weak SAI Pump, partially operative SAI valves and small Vac leaks conspiring ,cumulatively to cause the Readiness issue.Yes, it is rather vague and I think poorly understood . One diagnostic technique I have found useful is to note when the CEL comes on. Yes, it may require 3 starts to trigger the CEL but I mean does the light come on during cruise(Drive Cycle procedure) or about 2 minutes after a cold start ? If is comes on soon after the SAI pump shuts off after the cold start, I speculate that incriminates the SAI system,not the Cats.This may seem a trivial distinction until you see the price of a pair of new cats. If it is the SI system there is lots on Renntech about how to tediously plod through the dagnostics. I hope you are not up against Smog Test deadline. The Dealer can force the System "Ready" and immediately do a Smog Test for you -but nobody explains precisely what system/technique they use to do this. And the CEL may return quickly after the test.

Thanks Schnell. Ahsai made some of the same points and pointed me towards a scanner that can display the tests on my phone in real time. I'm hoping it will make things more specific. There are no CELs or stored errors. After 800 miles of driving, I would've thought a CEL would have come on by now - so I think it might be the nature of my commute and driving behavior - or so I hope (vs having to replace anything). Where in LA are you? I feel that I owe you at least a beer after all the times you've chimed in. Edit: Forgot that Ahsai mentioned the Mk II does not reset after disconnecting the battery. So a more plausible explanation would be marginal hardware component which hasn't been tested enough to trigger a CEL., Either way (maybe due to my driving style), hoping the scanner points it out. Also going to double check the SAI connections and the intake boot. Listening closer, it sound like there may be vacuum leak, but could also be my ears playing a trick on me.

After I had my IMS and a new battery installed I had to go through the readiness procedure. Followed it to a T and worked within 100 miles. Idle Car after sitting overnight for ~2 mins. Drive at 20-30 mph for around 3-3:30 mins. Drive 40-60 for apx 15 mins Decelerate to stop Idle in Neutral (if manual) for 5 mins Park (if auto) DO NOT EXCEED 3k RPM or 60MPH. I was golden after doing this.

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FWIW (probably not much), I've been having this same problem while trying to get my dad's '05 Mini Cooper S ready for smog. No CEL, no codes, just a persistent "catalyst monitor" error. Even after putting the stock header and cat back on followed by lots of slow freeway cruising, still no changes. So frustrating! Anyway, I have the GoPoint OBD reader and their app is great for monitoring stuff. You can even log every parameter it reads and export it for later analysis in your favorite spreadsheet software. Super useful, though it still hasn't pointed me to the solution...

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That's the 993 cycle. I read that it needed to be done strictly and sequentially for the 993 - not sure if it's true. From what I read and am told, doing this for the 996 also works...but you don't need to do it sequentially or at the specific intervals - but you need keep the RPMs and speed low. Where I live, I'm not sure I'm going to be able to do all of this. I going to get the scanner and try to get these cleared without being so stringent to the cycle guidelines. Otherwise, I think I'll have a strong case for the referee.

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I managed to do it in Atlanta morning traffic. 993 or not IT WORKS. I drove 400 miles without knowing that this was a procedure that had to be followed and then went to register the car (needed emissions) and failed because OBII not ready. Found this procedure, followed it that day and then immediately passed. It sucks, it's a pain in the *** and almost impossible to do, but it works.

The problem with the Drive Cycle anecdotes is that they are just that ...anecdotes. They work for some but not others.It is the "others" we are trying to help. On Renntech I linked to 6 different Drive Cycles.None worked.Eventually it went "Ready" .I have no idea why/how. Some engines just do not respond promptly. Which is why I hinted that just repeating the same (ineffective) procedure may be futile. It may be a more productive strategy to start testing components ? The check valves are not expensive and the silicone tubing and brass fittings are also inexpensive.Do the Vac accumulator also.Smoke test everything many times. When you count the hours to get in there, you'll understand why.If your Smog Test window& Stickers expire during this period you will be CHiP Bait This issue can land you in a world of mess beyond simple car mechanics. On quirky procedure that I have noticed may help with a marginal SAI system is limited to the 90 second Cold-Start stage. Try to drive and run the engine just as close to 3k rpm but without exceeding 3k.while the SAI Pump is running.I speculate that this may work because of the much higher volumes of exhaust flowing through the tired,old Cats. If your CEL tends to come on at around 2 minutes after a Cold-Start, this may be a hint? Using a GoPoint or similar is potentially a great diagnostic tool but don't be a Distracted Driver ! Ahsai has some threads where he discusses similar devices.

[QUOTE=mrjonger;14639083] Thanks Schnell. . Where in LA are you? I feel that I owe you at least a beer after all the times you've chimed in. You are welcome. I hope the M96 community can come up with a universal fix/hack for this thorny issue. Particlewave had a hack gizmo to do this. Did you see that Thread? Beer ? As a dedicated M96 enthusiast ,my preferred libation is Joe Gibbs - straight :-).

Lol at JG straight. I did not see that article, do you have a link? There are no CELs. And there are not stored codes either. I checked the engine and notices the intake boot and the tubing the SAI seemed to be on good enough, but were not at as snug as I would have liked. Did some adjustment on that. I am officially past due as of today. The couple of times I missed it, it just usually results in parking tickets - mostly at the airport and the actual city of LA, not the suburbs. I've never been pulled while actually driving. That being said, I'm usually on a motorcycle which is current, so not really worried. I came across this site. https://www.smogtips.com/smog-question/2692/Porsche-911-Emission-Monitors-Not-Ready. I don't think any of my normal driving emulates any of this. Particularly the catalytic converter piece. The scanner should be arriving today. Porsche 911 Drive Cycle - OBDII Emission Monitor Reset Procedure Prior to starting the driving cycle ensure your Porsche's fuel tank is between 1/4 and 3/4 full. Also do not exceed 3,000 rpm or 60 mph during any portion of the drive cycle. Take extra caution when perform the Porsche drive cycle on public roadways. if you think you will be unable to safely perform the drive cycle please seek assistance from an experienced Porsche mechanic or smog check repair center. A. Start your Porsche 911 and let it idle for approximately 2 1/2 minutes. This will allow the ECU to diagnose oxygen sensor aging; meaning the computer will be monitoring the oxygen sensor warm-up period and reaction to rising exhaust temperatures. During this period the ECU is also testing the Secondary Air Injection system. B. Begin driving. Accelerate to 20-30 MPH and maintain your speed for 3 1/2 minutes. The ECU will be testing catalytic converter efficiency. C. Next, accelerate to 40-60 MPH. Once again maintain steady speed, this time for approximately 15 minutes. The EVAP system is now being tested along with adaptation range (2) and the oxygen sensor (switching). D. Decelerate and come to a complete stop. If equipped with a manual transmission, idle in neutral for 3 minutes. If equipped with an automatic Tiptronic transmission, idle in drive (D) for 3 minutes. Adaptation range (2) is now being tested. E. Repeat steps B through D. Drive cycle complete.

I had the same issue with a not ready code. A week and 200 miles of regular driving wasn't enough to clear it. Finally I went out at midnight when the roads were empty and tried the below driving procedure that I found on the Pelican forums. I believe it worked on the first or 2nd try. It's very similar to the above, but with some specific instructions on limiting speed, RPM, and rapidly changing throttle angles: Start engine, idle cold for approx. 2 min, 10 secs. Accelerate to 20-30 MPH, Maintain steady speed for approx 3 min, 15 secs. Accelerate to 40-60 MPH, Maintain steady speed for approx 15 mins. Decelerate and come to a stop. Idle in gear for approx 5 mins. Following the start engine phase the sequence of test conditions may interchange. routine will be discontinued whenever: Engine speed exceeds 3000 RPM Large fluctuations in throttle angle Road speed exceeds 60 MPH

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I just moved to Denver from New York and purchased a new to me 996. Went to Air Care and failed twice. After much research I found this thread and it was the golden ticket. I bought a cheap OBDII scanner on amazon so I could see was and wasn't ready. The AC rear defroster combo worked for my evap monitor and I followed the drive cycle twice back to back and went back and that took care of the Catalyst monitor. After another nerve racking wait I finally passed! Thank you all for posting your experiences and I hope this helps someone else in the future. Happy driving!

hanks for keeping this Thread alive and all the info in one place. It really helps having one location instead of it being scattered among many new posts.. The whole "Not Ready" subject is complicated and often urgent because of Smog Testing. So sharing fixes(and failures) is a great service to Members. Thanks for sharing

Well shucks, I have to do this after I cleared some codes 2 weeks ago. Cat not ready. Gonna have fun driving under 60mph on an LA freeway, probably will be ran off the road, will report back.

My car seems to take about 250 miles to pass everything. Thats with mostly normal freeway driving and some residential driving.

Your fuel needs to be above half tank ,but below full also .If there's to much or to little it can affect the self test being done during drive cycle .The computer uses fuel vapor from evap system to test operation of fuel control systems .

Also, if some components are marginal the ECU will need more time to set to determine if that part is a pass or fail. High flow/aftermarket converters can cause this because they are less efficient than the OE units.

Just came across this thread full of great anecdotal info regarding monitor readiness. I'm running into an issue where the Catalyst monitor in my 997.1 C2 refuses to go ready. All other monitors are OK after a couple drive cycles. Would hugely appreciate any advice! Here's my thread in the 997 forum: https://rennlist.com/forums/997-foru...not-ready.html

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Drive it more. At some point the ECU will make a decision to pass or fail. The longer it takes the more marginal the system is.

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When you say the ECU "will make a decision to pass or fail" - what does this mean? Should I expect a CEL to come on eventually if the cat monitor continues to be incomplete?

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You should only see the check engine light triggered by this if the cat monitor test is deemed by the ECU as a fail. When it's incomplete the ECU hasn't made a decision yet. Unless there is something wrong with the ECU, this means that it needs more time to monitor it to make the decision to pass or fail it. Ultimately just drive it more until you see a pass or a fail.

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Hmm... the user manual for the Bosch OBD2 scanner says the only possible outputs are OK, INC, or N/A - there's no FAIL output. Are you saying that a CEL would represent a FAIL even when the scanner still shows the monitor as INC?

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My scanner has a Pass and a Fail option. Not familiar with the Bosch scanner but regardless, the ECU hasn't yet completed the analysis to determine if the system is a Pass or a "Fail". The end results are either Pass (OK in your case) or the check engine light gets triggered and a code is stored. Either way, unless something is wrong with your ECU, you need to drive the car more until either of this happens.

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You're giving me hope! I'll drive the car more and hope for the cat monitor to clear. Do you know if I can keep the scanner plugged in and keep an eye on the monitors during the drive?

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That's what I did with mine but it wasn't a Bosch. It's not going to hurt anything if it stays plugged in.

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Excellent, thanks for the help. I'll report back after driving some more.

Just going through this myself. I read all the threads. Honestly the driving part of the protocol is impossible to follow in any city due to stop signs, traffic, people walking dogs, lights, etc. The important parts from what I can tell are the idle on startup (which I never do). At just over 2 min the SAI pump turns off. I�m positive the ECU is checking this. For the driving I did them in aggregate. I got over 3 min at 20-30 in my neighborhood (stop signs and dog walkers not offended). I then made my way to the highway and rode the far right lane at 50-60z. Keeping the engine below 3k all the time. I then idled 5 min after the drive and viola green light in my code reader. The keys are do the idle time, do the drive time totals and stay below 3k rpm and no big throttle inputs.

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Its also important to have fuel tank between half tank and 3/4 .Low fuel makes it harder for the emissions to test itself.It uses evap system to interject fuel vapor into the intake and watches the operation of the cat and the o2 sensors.To much fel it gets to much and o2 sensors reading are not what is expected as is cat operation.

So I went to get my car smog today after putting about 450 miles on my new motor. They said the OBD scanner said one of the monitors had not set yet. So I took the car out and drove it for 15 minutes at freeway speeds below 3000 RPMs. I came home and use my Icarsoft POR2 monitor and round the iamb test for admissions. There were two items that came back as N/A. They were �Heated Catalyst Monitor� and �EGR and/or VVT system monitor�. I dont believe we have heated catalysts, do we? Regarding the EGR VVT system? Do you think �N/A� is just the readers way of saying the monitor is not set yet, or do you think it would indicate the EGR valve is bad. NOTE: there is no CEL and no codes.

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Hi, how did you end up getting these two monitors ready?

Hi Ertwert - if you do a few searches about how to clear the monitors for smog, there are a number of sequences that are recommended that are all pretty much the same. If I recall correctly, my mechanic said the one that is really hard to trip is the one where you have to idle for a total of three or four minutes while in gear. I don�t know if that�s at one time or a total combined time but I just held the clutch in and let the engine run. It was painful, but it seem to work. The other thing was driving on the freeway at a constant 50 to 55 mph without rubbing over a certain RPM. I just got on the freeway a few miles out of our town where there wasn�t much traffic and set cruise control. Just do a search on this forum or on the Internet for resetting smog monitors for Porsche and you�ll find the common protocol. good luck.

the sequence absolutely works in a 996 I drove ~300 miles after a failure only to fail again Looked up this thread, followed the sequence to a T, and passed. This should just be common practice after disconnecting the battery. Some people may complete the sequence daily driving. But not me. It was near impossible to keep it under 60.