Guide: Found a successful Drive Cycle formula!

5

50poundbrain

Member
:
1996 626 DX
Will it solve your problems? I don't know, but it worked for me! I did have to run it twice to clear everything but "Catalyst", but Utah allows one I/M sensor to be "Not Ready" and still pass inspection. I also "Faked" a cold soak by hooking up a 0-1000 ohm variable resistor in series with the coolant temp sensor so I could run a drive cycle, shut the car off, put the full 1000 ohms resistance in the temp sensor circuit (the ECM then thinks the engine is cold), turn the resistor form 1000 down to 0 ohms (now reading the actual temp sensor signal), and run the drive cycle again. From a Miata forum I found via Google:

Here is a Mazda drive cycle:

Pre-requisites: MIL off and no DTCs present (this is where clearing your codes comes in); fuel level between 15 and 85%; all accessories OFF; cold start (preferred 8 hour cold soak w/ engine between 68 and 86 deg F at start-up)

1) Start vehicle and idle 5 min.
2) Rev engine in neutral or park to 2300-2700 rpm for 15 seconds
3)Rev engine in neutral or park to 3800-4200 rpm for 15 seconds
4)Idle engine for 20 seconds with cooling fan stopped.
5)Accelerate to 52-55 mph, maintain speed (in high gear) for 1 1/2 minutes
6) Decelerate to 15 mph, and then drive for 13 minutes at speeds ranging from 15 to 35 mph
7) maintain steady 25 mph for 50 seconds.

Each step of the drive cycle indicates a test for a different monitor on the vehicle (catalyst, o2 sensor, evap, etc) so each step is important. Some vehicles are a pain and may require a few drive cycles.
 
50poundbrain said:
Will it solve your problems? I don't know, but it worked for me! I did have to run it twice to clear everything but "Catalyst", but Utah allows one I/M sensor to be "Not Ready" and still pass inspection. I also "Faked" a cold soak by hooking up a 0-1000 ohm variable resistor in series with the coolant temp sensor so I could run a drive cycle, shut the car off, put the full 1000 ohms resistance in the temp sensor circuit (the ECM then thinks the engine is cold), turn the resistor form 1000 down to 0 ohms (now reading the actual temp sensor signal), and run the drive cycle again. From a Miata forum I found via Google:

Here is a Mazda drive cycle:

Pre-requisites: MIL off and no DTCs present (this is where clearing your codes comes in); fuel level between 15 and 85%; all accessories OFF; cold start (preferred 8 hour cold soak w/ engine between 68 and 86 deg F at start-up)

1) Start vehicle and idle 5 min.
2) Rev engine in neutral or park to 2300-2700 rpm for 15 seconds
3)Rev engine in neutral or park to 3800-4200 rpm for 15 seconds
4)Idle engine for 20 seconds with cooling fan stopped.
5)Accelerate to 52-55 mph, maintain speed (in high gear) for 1 1/2 minutes
6) Decelerate to 15 mph, and then drive for 13 minutes at speeds ranging from 15 to 35 mph
7) maintain steady 25 mph for 50 seconds.

Each step of the drive cycle indicates a test for a different monitor on the vehicle (catalyst, o2 sensor, evap, etc) so each step is important. Some vehicles are a pain and may require a few drive cycles.
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Followed steps for my 2012 cx9 and it worked! Thanks for the awesome tips!
 
Thank you Internet Strangers. This was so helpful. For “idle with the cooling fan off” I just turned off the heater and a/c.
 
In that exact order, yes, has been my experience. However, I've sometimes had to pause in between each step because of traffic or road conditions but I've done it all in that one drive. I've driven more time that what the cycle recommends (by a few minutes), once again because of traffic and such, but it hasn't negatively affected the outcome. I have noticed on my Protege I have to do it more than once for it to ready set the sensors.
 
Hi everyone...

A number of years ago my autoshop gave me the drive cycle specifications for my 2008 Mazda.

However, I have continued to struggle with triggering the drive cycle and getting my car through DEQ. And no one has yet been able to explain this to me.

-Check engine light is not on.
-Battery is fine. I don't need to jump it in order to get it to start in the morning.
-The autoshop didn't identify any underlying issues a number of months ago when I had the oil changed.
-According to DEQ my car has no codes. So all indicators point to no mechanical problems.

There must be some small detail or unwritten assimption I am not understanding.

Am I suppose to run the heater and / or fan while the car is idling and then rev the engine?

Do I have to rev the engine for exactly 15 seconds? Does there have to be enough variation while staying in the RPM range specified?

Does "decelerate" mean brake hard or gradually slow to 15 miles per hour and then drive between 15-35 for 13 minutes? If I hold a steady speed of 25 miles per hour fir the duration..is this bad?

With an analog speedometer, how can I be sure I hit exactly 15 miles per hour? Does it have to be 15 exactly? Do I have to hold it at 15 for a few seconds or longer before varying my speed between 15-35?

I am so frustrated and tired of this being such a dramatic event every two years. Over the last 6 years. I have been pulled over for expired tags.

This needs to end. I would like to KNOW how to do this without paying an autoshop to do it for me.

Thank You.
 
This drive cycle is for a Mazdas 2003 and older. I know this works on my 2001 Mazda Protege.

It took a bit but I was able to find this link for the Mazda 3s.

Disconnected battery, failed OBDII inspection. Do we...

Scroll down and find the posts by flatlander937. Focus on the parts in bold and pay no mind the PID scan tool unless you own one of those. Some of those instructions repeat themselves so you may have to piece it together to help it make sense.

The other thing you could do is drive for 50-100miles in several different types of traffic. From normal morning traffic to highway traffic to help all the sensors set. This is what I used to do until I learned about the drive cycle for my Mazda Protege.

If you have one of those OBD2 scan tools, you can see if yours will tell you when all your sensors are set. Hope this helps.
 
Last edited:
AzteCypher said:
This drive cycle is for a Mazdas 2003 and older. I know this works on 2001 Mazda Protege.

It took a bit but I was able to find this link for the Mazda 3s.

Disconnected battery, failed OBDII inspection. Do we...
Disconnected battery, failed OBDII inspection. Do we...

Scroll down and find the posts by flatlander937. Focus on the parts in bold and pay no mind the PID scan tool unless you own one of those. Some of those instructions repeat themselves so you may have to piece it together to help it make sense.

The other thing you could do is drive for 50-100miles in several different types of traffic. From normal morning traffic to highway traffic to help all the sensors set. This is what I used to do until I learned about the drive cycle for my Mazda Protege.

If you have one of those OBD2 scan tools, you can see if yours will tell you when all your sensors are set. Hope this helps.
Click to expand...
So, here's the thing I have driven more than 1,000 miles since getting pulled over for my expired tags. I have driven long distance putting 80 or more than 100 miles round-trip multiple times. I incorpate speeds of 50-60+ MPH with slower speeds of 15-35 MPH and city driving of 30-45 MPH.

The drive cycle specifications the autoshop gave me seem to exactly match what the internet says it should be. I hate that there doesn't seem to be an organization responsible for cataloging this and who can give definitive answers since being able to pass DEQ is mandated by law if you have a vehicle.

When I get home I will post the exact drive cycle specifications here to get any additional feedback.

I have an appointment Monday to get my car looked at, but I don't think they will find anything wrong.

Thank You.
 
Oh wow! That should've definitely done it by now. So is the inspection station telling you that can't pass inspection because your sensor's still aren't set?

We might be able to guide you a bit better once you've posted the drive cycle specs. What state are you in if you don't mind my asking?
 
Yes, multiple sensors say they are unready:

Catalyst
Evap
O2 Sensor
EGR/VVT

Smoke test: Pass

If each step of the drive cycle corresponds to a different sensor and the must be done in sequence, why are 4 unready? Why aren't more unready if each step is critical to triggering the drive cycle? Shouldn't be all or nothing?

88888

This is exactly what my autoshop gave me for the cycle specifications (see below).

Pre-requisite: MIL off and no DTCs present (this is where clearing your codes comes in); fuel level between 15 and 85%; all accessories OFF; cold start (preffered 8 hour cold soak w/ engine between 68 and 86 degrees F at start up)

1) Start vehicle and idle 5 min.

2) Rev engine in neutral or park to 2300-2700 rpm for 15 seconds.

3) Rev engine in neutral or park to 3400-4200 rpm for 15 seconds.

4) Idle engine for 20 seconds with cooling fan stopped. (If the fan has to be stopped that would imply it needed to be turned on at the beginning. Does it also need to be turned on after the 20 seconds? Does the fan / ac have to run, but not the heater, or does it not matter, so long as one is running?)

5) Accelerate to 52-55 mph, maintain speed (in high gear) for 1 minute and 30 seconds.

6) Decelerate to 15 mph, and then drive for 13 minutes at speeds ranging from 15 to 35 mph. (If at any time we go above or below the threshold or come to a complete stop is the entire run lost, or do we just start this step over? There aren't many places where you can cruise uninterrupted at these speeds without a stop sign, red light or drivers getting impatient and wanting to drive faster.)

7) Maintain steady 25 mph for 50 seconds. (At this point do I shut off the car immediately or as soon as it's reasonable?)

Is there a a maximum time limit between starting the different steps? Is there a fixed period of time to go through all the steps?

888

I live in the state of Oregon in the USA.

Do I need to go on another road trip after multiple attempts at triggering the drive cycle?

Any feedback would be appreciated.

Thank You.
 
Just so I understand correctly, your check engine light isn't on after driving those 1,000 miles, correct? You mentioned that it wasn't on but I wanted to verify.

Below are the only additional notes/tips I can offer and I apologize for the extended reading material:

For any step specifying the number of seconds or minutes to maintain such step/procedure, it's always ok to go over the time specified but never go below the time specified. Anything less than the minimum amount of time will not let the sensor set. Use the clock on the radio to maintain the time rather thank checking your watch or your phone. I find this more convenient but do what works best for you.

I don't remember the exact percentage of fuel necessary to run through this drive cycle but I think I can safely estimate that your fuel tank needs to be between 20% - 80% full. Anything outside of that range might negatively affect the results.

For step 1, idle for 7 minutes just to be sure.

For step 2, try to aim for 2500 rpm. It doesn't have to be exact but it does have to be between 2300 rpm and 2700 rpm. If you aim for 2500 rpm, odds are you won't deviate by more than +/- 200rpm when trying to maintain the accelerator at those rpms. I would aim for 17 seconds just to be sure.

For step 3, same as above, but aim for 3800 to account for some deviation. Once again, aim for 17 seconds just to be sure.

For step 4, IF you hear the fan kick on after you're done with step 3 wait for it to stop before proceeding. If the fan is not on, proceed with step 4. You don't have to wait for the fan to kick on then off again. The important piece in step 4 is to make sure the fan is off before idling for 20 seconds. I'd count to 25 just to be sure. Neither the heater nor the a/c need to be on.

For step 5, aim for 53 or 54 mph for the reasons stated above. I would maintain it for 1min and 45 sec. If you can, try to maintain this speed with cruise control. I believe the PCM is looking for a consistent load with minimal throttle input.

For step 6, I would decelerate without any brake input. Let it coast to 15 mph. Once you reach 15mph, maintain that speed for 3 min, increase to 20 mph and maintain for 3 min, increase to 25 mph and maintain for 3 min, increase to 30 and maintain for 3 min, increase to 35 mph and maintain for 3min. By doing it this way, you will have driven within this range for 15min, longer than the required 13min.

If you have to come to a stop during step 6, I'm not sure if you have to restart step 6. For this reason, I would try to find a road that will permit you to do this and try to do it later in the evening. I usually attempt these drive cycles after 8:00PM and use my hazards so that hopefully people get the hint and just go around me.

For step 7, I would maintain that speed for 1 minutes but you don't have to shut the car off. You can just drive home after this.

I wouldn't say there's a time limit per say, but I try to get all the steps done in one outing though in the past, it's taken me 2 or 3 tries before it takes. Remember that the PCM is looking for specific parameters to be achieved such as temperature, consistent load, throttle input, etc. During the normal course of driving 50 - 100 miles, all these sensors are normally set because you've achieved the above mentioned drive cycle over the due course of time. Once a certain set of parameters are met, the sensor that those parameters apply to, are set. This is why I find it very odd that after driving for so long, you still have sensors that aren't in a ready state.
 
Update:

I had my appointment today (Monday) to get my car looked at.

In summary:

Despite no check engine light and no codes, they told me one or multiple sensors were bad. It was failing, but not failing enough to trigger something to indicate there is a problem. Schrodinger's sensor?

All the driving I did was worthless, I never had a chance of triggering the drive cycle.

I obviously wanted to know what they did to trigger the drive cycle and what I essentially got is my car was driven around at a speed of between 40-50 mph, 40-55 mph? Ok, just drive it around at the speed for a long enough distance, shut the engine off and let it cool for 8 hours and do it two more times--is this it? Is this all?

I will be relieved when I have the piece of paper in my hands that says my car is passing.

And when I am more calm I will reference the various threads that have been linked, print them off and keep them for future reference.

Apparently, ALLDATA is a website that provides technical specs and information, but it's jargon heavy and something a lay person would struggle to understand and likely find incomprehensible.

I suppose for a fee I could find the information for my car and search for articles, resources or books to help me make sense of it.
 
Did they at least tell you which sensors were going bad so you could replace them down the road?
 
AzteCypher said:
Did they at least tell you which sensors were going bad so you could replace them down the road?
Click to expand...
Update:

Sorry for the delay.

Looking at the receipt from the auto shop the Air Fuel Ration Sensor and Rear Oxygen were reading slow and would not perform the monitor test. If I recall correctly my car was basically in a state of "still warming up" according to the sensors. And I was told these go bad at around 90K miles.

My car is passing thankfully.

I am disappointed I didn't get a printout of the information my auto shop used to complete the drive cycle, but it's entirely plausible that they can't share this with me and / or an explanation in simpler terms for a non-mechanic because it would be a violation of the terms and conditions of accessing ALLDATA.
 
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