Drive Cycles

My 2000 Sonata flunked the California smog test. I have a code reader, which showed no stored codes. I failed to note that three of the monitors had completed their sequences.
I took it into the smog shop, where it passed all the emissions requirements, but failed due to a loose, leaking hose between the two valve covers, which had prevented one of the monitors from completing, and failed the visual inspection.
I replaced the hose, then ran the two drive cycles to satisfy the monitors that all the sensors had been put through their tests and had replied properly. Again, there were no stored codes.
The monitors can do their thing eventually just from normal driving. However, they need lots of that normal driving, and when one's in a hurry, one does the drive cycles.
I understand that Hyundai won't release these routines. I was able to find them a few years ago. I had a long phone conversation with a guy at the State air resources board, who recommended that I go into a smog shop and check their copy of _Motor's Drive Cycles._ And, lo, therein I found the slow and fast cycles for a whole range of Hyundais of many years.
Performing these tests is quite a challenge, especially if there's any traffic on the road, red lights, or stop signs. It's pretty hair-raising and takes two people, one to read the instructions out loud and hold the stopwatch; the other to drive the car.
There are 15 and 16 steps on each of the two drive cycles. Here is one of them from the _highway_ routine: "Accelerate moderately. Drive at 20-25 mph for 20 seconds. Increase speed to 40-55 for 85 seconds, then decelerate to 0 over 60 seconds. Idle 15 seconds." Now, just visualize how you will carry this out on a hilly, curvy two-lane road with some shoulders, light (but real) traffic, a couple of traffic lights, and three stop signs, all the time looking in the mirror for oncoming vehicles.
I made lots of errors, especially by overrunning the top speeds of the steps and misjudging the alotted time for each accelerate/decelerate interval.
Amazingly, all three of the outstanding monitors were satisfied. And I passed the (free) re-test.
This is the second time I've had to do this. I discussed the wild ride with the smog technician. He said that VWs and Nissans have cycles that are just as insane. I figured that nobody can perform these tests safely or accurately on real roads, and that they can only be done, practically, on test tracks or dynamometers (just like our smog stations now are required to use).
The shop owner said that she's never heard of anyone running these routines on a dynamometer, and there not many test tracks in my neighborhood.
So, if a person needs to get these monitors completed and doesn't have the time to do 100 miles of regular driving, what's a rational way to perform these routines?
I'm truly stumped.
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wrote:

Everyone else is stumped, too. The dealer can command the EVAP test to run. Other than that, they'll run only by driving the car.
I think the thing they're not telling you is that certain conditions are necessary for certain tests and that some tests need to complete before others can complete. So in some cases, you may not need to go through the whole drive cycle, just complete all the necessary components for the test(s) in question to run. To my knowledge, a procedure for running any specific test (other than the EVAP test), is not published anywhere.
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hyundaitech wrote:

Hi, HT.
I recall that we discussed this a couple of years ago, and you mentioned that the manufacturer doesn't even make this information available to their own dealer shops. Perhaps their lawyers were behind this. Imagine the claims and lawsuits that would result when people actually tried to perform these routines as instructed, causing road accidents.
If a California State employee hadn't told me where to look, I would have never known how to run these routines. This last time, I would have been out real money since by the time that my monitors had been reset in normal driving, my plates would have expired and I'd have had to pay a stiff extension fee.
Due to the whole rigmarole last time, I wound up being interviewed by, and quoted in, U.S. News and World Report for a piece on code readers, which I recommend that everyone own. It's a great reality check against the dreaded "Check Engine" light. I especially like the one that's sold under the name Equus (I forgot who the actual manufacturer is). Its usability is greatly better than the other two that I tried (and returned). The manufacturer is Taiwanese, with engineering and support done in California.
In the course of my research, I gained true respect for the electronic engine control systems and what they do for us. They can be a real pain, and so much of modern automobiles make them next to impossible for us to repair ourselves. It's a dilemma. Yet it's obvious that they stretch our fuel efficiency and also dramatically improve the air that we breathe (our own internal combustion).
I don't know why some smog shops have a copy of _Motor's Drive Cycles_ but that's where I found the routines. Don't knock Government employees, guys: there are good ones, and they can really come in handy! This is a huge bound book. And it saved my ass.
Well, maybe one or two of you will desperately need to reset your car's computer this way the way that I did, and maybe you'll be able to use this information. But do this someplace where the conditions are like a test track. Where is this? I have no idea!
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