OBD2 Readiness

1)  Is there a way to tell with an OBD2 Bluetooth dongle & app if my car is 'ready'?

2)  Is the drive cycle to reset readiness monitors the same for all makes (part of OBD2 standard), or is it going to vary from car to car?  Ford publishes a guide to completing the drive cycle.  I haven't seen other manufacturers do this.  Certainly nothing from Nissan circa 2003.

Our rallyx car was 'not ready' when we took it for emissions testing.  We have corrected an issue that was throwing codes, but I want to be sure it is ready when we take it back.  But, as the car is not currently legal (lapsed registration), I want to minimize the amount I have to drive it to get it ready.

Mazda and GM both have published "short cycle" readiness monitor test runs; not sure about Nissan.  Be forewarned that they can sometimes be very specific and difficult to follow.  I never did get the Manic Miata to pass readiness in Depressive Mode.  I eventually just paid the fine and got my card.

The long cycle that will check all codes is the FTP75.  If you can drive something very similar to that, it will check all the codes during the test.  Long is relative- it's only 10 miles of driving.  But it does take 30 min to do it.

alfadriver said:

The long cycle that will check all codes is the FTP75.  If you can drive something very similar to that, it will check all the codes during the test.  Long is relative- it's only 10 miles of driving.  But it does take 30 min to do it.

Doesn't it take more than a single cold-start to check startup systems?

I can replicate FTP75-ish (less frequent stops, so I'll have to increase drive length to get them), but how can I make sure the car is ready before going to the emissions station?  Because if it isn't ready its a huge waste of my time.

1. Yes torque has an emissions readiness screen you can bring up.  I am sure other apps have something similar.   If they are not ready they will show as not ready.  Check your state regs for how many not ready you can have at inspection time.  VA is 2 not ready for 1996-2000 and 1 not ready for 2001+

ProDarwin said:

alfadriver said:

The long cycle that will check all codes is the FTP75.  If you can drive something very similar to that, it will check all the codes during the test.  Long is relative- it's only 10 miles of driving.  But it does take 30 min to do it.

Doesn't it take more than a single cold-start to check startup systems?

 

I can replicate FTP75-ish (less frequent stops, so I'll have to increase drive length to get them), but how can I make sure the car is ready before going to the emissions station?  Because if it isn't ready its a huge waste of my time.

All should be set and cleared in two full cycles. 

As for reading it, if you can check codes, you should see that the monitors have all run, since there's a code if they have not.

Thanks.  Moxnix - I was able to find a similar screen in the app I use (OBD Fusion) finally.  It even has the state regs built into it.  I'll check tonight when I get home if it will do the trick.

I used torque and this list for mine

https://trackdogracing.com/OBDII.aspx

Ugh.   I tried some variations of that, what others posted in Nissan forums, and a bunch of general driving around.  

I can't get the catalyst, oxygen sensor, or evap codes to reset.

I'm guessing the catalyst has to do with the secondary o2 being in an aftermarket header that has no cat, with a spacer bung under it.  Is it possible for something to not trigger an O2 code, but never reach readiness?  I may have to extend the wires and put a bung in behind the lower cat.

Any ideas why evap wouldn't report ready?

May be a semantic problem here. Complete as a word doesn't tell you whether it passed or failed. Is there a chance they are complete and simply failed, thus the red X?

In reply to ProDarwin :

Most catalyst and O2 sensor checks use both sensors to see what's going on.  For instance, the front sensor may put in a specific big pattern that should be noted through the catalyst, and if it doesn't see it, it can't check it.  For sure, the catalyst monitor uses the second sensor- somehow.

So taking the second sensor out of the stream will certainly mean it can't run the monitor- or more correctly, can't finish it.  So, yes, you should find a way to put that sensor back in.

In reply to Vigo :

If any of these tests failed, you'd get a bright yellow MIL.

Might even want to put a cat back in. Modern cats have virtually no effect on power and make being around the car when it is running much nicer. If you are running a muffler many times putting a cat in will make a muffler not necessary. Sometimes they actually make the car run better.  The closed loop versus open loop.

https://grassrootsmotorsports.com/forum/grm/catalytic-converter-face-off/104628/page1/

By doing this you get a car that is actually running right is legal and smells better and you will not have to spend all the time messing with things trying to fake out the computer. In the long run it may actually be cheaper ant it will save you time now and time down the road . I don’t see a down side to running a cat here.

dean1484 said:

I don’t see a down side to running a cat here.

I have a cat.

The car from the factory has 2 cats.  One in the header, one in the down/midpipe.  The one in the header degrades, gets sucked into the engine, and causes engine failure.  This is a widely known issue with Sentra SpecVs.

If there were a way to restore that cat without worrying about it taking out the engine I would consider it.  Looks like moving the secondary O2 to behind the cat is my best option... I just need to figure out how to do so without making the wires long enough that they throw off the voltages.

I'm still not sure why EVAP isn't checking out ok.

I had to do this over and over .......2003 Caddy CTS, to get it ready for NYS inspection.

General Motors Driving Cycle

A complete driving cycle should perform diagnostics on all systems. A complete driving cycle can be done in under fifteen minutes.

To perform an OBDII Driving cycle do the following:

1. Cold Start. In order to be classified as a cold start the engine coolant temperature must be below 50°C (122°F) and within 6°C (11°F) of the ambient air temperature at startup. Do not leave the key on prior to the cold start or the heated oxygen sensor diagnostic may not run.
2. Idle. The engine must be run for two and a half minutes with the air conditioner on and rear defroster on. The more electrical load you can apply the better. This will test the O2 heater, Passive Air, Purge "No Flow", Misfire and if closed loop is achieved, Fuel Trim.
3. Accelerate. Turn off the air conditioner and all the other loads and apply half throttle until 88km/hr (55mph) is reached. During this time the Misfire, Fuel Trim, and Purge Flow diagnostics will be performed.
4. Hold Steady Speed. Hold a steady speed of 88km/hr (55mph) for 3 minutes. During this time the O2 response, air Intrusive, EGR, Purge, Misfire, and Fuel Trim diagnostics will be performed.
5. Decelerate. Let off the accelerator pedal. Do not shift, touch the brake or clutch. It is important to let the vehicle coast along gradually slowing down to 32km/hr (20 mph). During this time the EGR, Purge and Fuel Trim diagnostics will be performed.
6. Accelerate. Accelerate at 3/4 throttle until 88-96 km/hr (55-60mph). This will perform the same diagnostics as in step 3.
7. Hold Steady Speed. Hold a steady speed of 88km/hr (55mph) for five minutes. During this time, in addition to the diagnostics performed in step 4, the catalyst monitor diagnostics will be performed. If the catalyst is marginal or the battery has been disconnected, it may take 5 complete driving cycles to determine the state of the catalyst.
8. Decelerate. This will perform the same diagnostics as in step 5. Again, don't press the clutch or brakes or shift gears.

Reprinted on OBDII web site courtesy of General Motors Corporation
© General Motors Corporation

[ OBD-II Home ]

In reply to ProDarwin :

As long as you use good quality crimp connectors, you are not going to throw off the sensor.  And seal them with some good heat shrink.

Vigo said:

May be a semantic problem here. Complete as a word doesn't tell you whether it passed or failed. Is there a chance they are complete and simply failed, thus the red X?

As an aside, the above reminds me of a story I heard that is both funny and very much not. A guy had a "defective" testicle removed and came out of surgery only to discover they'd removed the good one. Seems in prep, someone put an "X" on one of them. Now if you were the surgeon and saw an "X" on one, does that mean, "leave this one alone, it's the other one", or "remove this one."

Semantics can matter, sometimes a lot.

Man, unless you live out in the country, how are you supposed to do that readiness test?  Way too much traffic, stop lights/signs around me to do that here.

Yes, move your post stream O2's to after the catalytic convertor, bet that takes care of the issue.  The ECU is looking for a gradient delta change in readings between the pre and post cat O2 sensors...

In reply to docwyte :

That drive cycle is just the quick way to hit all of the test conditions.  If you just drive the thing normally for a while it'll usually set the monitors no problem (just not necessarily in a day). 

For the evap check to complete you may need to have a sufficient volume of fuel in the tank.  I ran into this issue not long ago.

Snrub said:

For the evap check to complete you may need to have a sufficient volume of fuel in the tank.  I ran into this issue not long ago.

Yes, some manufacturers have a range of fuel where the evap test will run.  Usually the tank can't be totally full.  Somewhere around half should be a safe bet, I think. 

If any of these tests failed, you'd get a bright yellow MIL.

Oh, duh. Totally forgot the context of the thread. lol! 

My '96 SE-R owners manual has the drive cycle close to the back page.  Check the owners manual you might get lucky.  I just wonder if the '96 will work on my '97 SE however.  

Havent had a chance to do the bung yet.  I did take a closer look at PID values tonight though.  Running temp never gets over ~161 when moving.  Swapped Coolant Temp Sensors and still reading that.  Looks like I need new thermostats.  Yes.  Plural. (WTF).

Anyway, I'm guessing it wont do the highway/fully warmed up checks because the engine is never hitting operating temperature.

Update:

Put in new thermostats.  Car now reaches a normal operating temperature.

Welded in a bung and extended O2 wire.  Drove around for 30 miles.  Tank was ~3/4-5/8 full.  The other O2 is now showing ready.  Still can't get catalyst or evap to show ready