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Smog test failed because computer would not show repair. How can I fix this

(2002 Kia Rio)
in Laguna Hills, CA on January 17, 2012
In Nov mechanic fixed indicator light that was on but car computer failed to acknowledge repair. Aside from driving it more, is there a way to fix this problem w/computer?
Displaying 3 answers & 4 comments
Popular Answer
Does the Check Engine Light come on when you turn on the ignition switch and extinguish when you start the engine? If so the computer is operating the light and there is no hard fault code stored. You need to use a scan tool that can determine which monitors are or are not yet passed.To get the car to pass the drive cycle monitors the car must be driven a certain way.
The following is a summary of generic OBD II drive cycle instructions The Intake Air Temperature (IAT) should be between 14 and 122 degrees F. Barometric pressure should be equal to or greater than 75 kPa. The fuel tank should be between 25 and 75% full at the start of the test. During acceleration, keep throttle 1⁄4 to 1⁄2 open. During deceleration, slow to less than 15 mph at an engine speed of less than 1000 rpm without touching the brake or clutch pedal. During cruise, maintain a steady engine speed between 1400 and 4000 rpm. At idle speed, keep the throttle closed and the gear selector in the Neutral position. Remember, these are just the preliminary instructions. The actual drive cycle must conform exactly to the following instructions, or the various monitors may not run to completion. The drive cycle begins with a cold engine startup. The IAT must be between 32 and 85 degrees F. Engine Coolant Temperature (ECT), must be less than 127 degrees F. It may be necessary for the customer to leave the car with you overnight so it can cool down completely. The engine coolant and intake air temperatures must be within a tight range to complete all of the OBD II monitors during the drive cycle. If the IAT input is not between 32 and 86 degrees F at the beginning of the drive cycle, the EVAP monitor will not run. Start the engine and allow it to idle in Park for one to two minutes. Within the first minute and a half, accelerate at 1⁄4 to 3⁄4 throttle to 50-55 mph. Hold that speed for 2-3 minutes. Unless your shop is very close to a major expressway, it may be difficult to satisfy this step in the drive cycle. Decelerate to 0 mph without braking, then idle for 1-2 minutes. If you’re on an expressway, pull safely off the road during this segment. Accelerate to 55 mph, using 1⁄4 to 3⁄4 throttle, then hold a steady cruise for 10 to 20 minutes. Return to 0 mph with the engine idling in Park, then turn the ignition off.
on January 18, 2012
I called mechanic re computer problem & he said that the computer had to re-learn the codes first before monitors could reset as had been erased - had to be done by themselves. Disconnecting the battery cables would only make it worse. He would have to have one of his technicians perform the 17 steps necessary on the hightway to do this otherwise will continue to fail smog computer test. The engine light no longer comes on as was fixed. I don't drive on the highway, but daughter will be driving round trip to San Diego about 60 mintues (staying overnight to cool engine - will this work? Had already done this trip a month ago. Thanks
If the repair was fixed he should have been able to reset the codes in the computer with a scan tool. If he didn't do that the codes will still be in the history and need to be reset. Your local auto parts store ie Advance Auto, AutoZone, O'Reilly will all reset the codes free for you.
on January 18, 2012
I called mechanic they did use scan tool after repair but codes were erased & he said that had to be re-learned/set & the only way was by driving it.I had originally received a 17 step procedure to do this, but a technician will have to complete this at least twice. Hopefully by driving on the highway for a roundtrip to San Diego (about an hr. each way) will work. Any other suggestions. Thanks.
removing the battery negative for about 10-15 min. should be sufficient to reset the computer stored codes
on January 18, 2012
Hi from Peggysue - I just called the mechanic who fixed the problem w/the engine light. He had done all that was required, however he told me that the computer has to re-learn the codes so monitors will set by themselves. The smog test computers failed to complete all the OBD self tests. I don't drive on the highway but did have a friend drive it to San Diego, which is over an hour each way. I'm planning to do that trip again but if it still doesn't work then I have to perform a 17 step program (twice) to reset the codes/monitors by themselves. No other fix-it will work. Does this sound right to you?
It should have reset. A combination of short trip and long trip driving (typical 50-75 miles) is all that is required. The vehicle also is looking for heat cycles (running vehicle till warm, then cooling).
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