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Failed Your Smog Check? “NOT READY” Failures or “Check Engine” Failures

Updated: May 10

How to Perform a Basic Drive Cycle to Pass your Star or Regular Smog Check Inspection after failing a test for “NOT READY” Failures or “Check Engine” Failures.

Before returning to Joe's Drive Thru Smog Check Star Station for your Star or Regular Smog Inspection be sure to accumulate a total of a 150 Freeway Miles at the Speed Limit posted signs 55 mph to 65mph.

For model year 2010 and newer vehicles accumulate a total of a 200 miles and completed at least 15 warm-up Drive Cycles Steps 1-4*.

Rest assured, you may repeat the smog check inspection as many times as you wish at Joe's Drive Thru Smog Check Star Station becuase the facility is a Pass or Don’t Pay® facility. You pay for a smog check if, and only IF, the vehicle passes the smog check. We do not perform repairs on vehicles and we do not refer customers to repair facilities because it is a conflict of interest. This means our customers get an honest and unbiased inspection from our facility.  As a NO Pass!No Pay!® facility, we do not have any incentive to fail or pass any vehicle.

You must perform a “drive cycle” after the repairs are performed, after a dead battery, or replaced battery before going back to the inspection station. This is done to complete the Readiness Monitors.

A Drive Cycle is a special test drive that duplicates a person starting their car and making a short freeway trip, as if they were driving to work (Example: An average of 150 Freeway Miles accumilated at the Highway Speed Limit). While this special test drive or 'Drive Cycle' is occurring, the Engine Computer runs little tests or Readiness Monitors that check to see if the Emissions System is working properly.

How to Perform a Basic Drive Cycle

Here are step-by-step instructions on how to perform a basic Drive Cycle that will complete the readiness monitors for your vehicle's emissions control system. The Drive Cycle is one of the methods used by the powertrain control module (PCM) to determine whether an emissions system repair was properly performed.

Tip 1 - How to Prepare Your Vehicle

  • Have the fuel tank between 30 and 70 percent full. Some systems, especially the EVAP system, need to have a specific level of fuel in order for the tests to be trusted. If the fuel tank is near empty or completely full, many of the basic tests will not run at all.

  • The vehicle must also have a good alternator and a strong battery. If you have to occasionally jump-start your vehicle, all of the memory from the powertrain control module (PCM) is erased, which includes the data that accurately tracks the results from various stages of the Drive Cycle. If the battery is weak or undercharged, some of the most important tests will not run.

  • The vehicle must sit overnight, or for at least eight hours, in an environment that is less than 90° F. The engine temperature needs to match the air temperature in order to establish an accurate baseline for the testing. If the outside temperature is over 90° F, the fuel is too volatile and the EVAP system won't even try to run its tests, though some of the other emissions systems may run their tests.

  • The keys must be out of the ignition and all of the doors must be closed while the vehicle sits over night because many of the onboard computers "boot up" when the keys are in the ignition. Also, many of the onboard computers still run until all of the doors are closed after the vehicle is shut off and the keys are removed. 

Tip 2 - The Cold Start

  • Start the vehicle and let it sit at idle for two to three minutes in Park or Neutral. Let the idle speed settle down to near the normal speed. 

  • Next, put the vehicle in gear and drive through city streets at about 25 mph. Go up to about 35 to 40 mph a few times before slowing down to stop. Don't roll through the stop, be sure the car is completely stopped. Accelerate from each stop in a normal fashion—not overly conservative, but not like you are competing in a drag race either.

*Please Obey All Traffic Rules & Perform Under Safe Conditions Only

Tip 3 - A Short Freeway Trip

  • After the vehicle has been cold started and driven for a few miles on city streets, the next step is to take it on a short freeway trip. 

  • Enter the freeway on-ramp and allow enough room with respect to other vehicles so that you can do a 1/2 to 3/4 throttle acceleration up to freeway speed. 

  • When you have accelerated up to around 60 mph and have safely merged into the flow of traffic, stay in the slow lane and maintain a steady speed of 55 to 65 mph for a minimum of Ten (10) miles "Obey All Highway Speed Limit Signs". Please use the cruise control to help you maintain speed.

*Please Obey All Traffic Rules & Perform Under Safe Conditions Only

Tip 4 - More City Driving

  • After you have completed the freeway trip, drive through the city streets for a repeat of the second part of Step Two. 

  • Go up to about 35 to 40 mph a few times and then maintain a city speed of 25 mph before slowing down to stop. Again, don't roll through the stop sign and make sure to accelerate normally.

  • Pull in to a parking place and let the engine sit at idle for one to two minutes and then shut it off.

Tip 5 - If MIL Check Engine Light Turns On

  • If  your check engine turns on, take your vehicle to your repair facility to have the vehicle diagnosed and repaired properly. Have the mechanic c

Tip 6 - Readiness Monitors Verified If Ready

  • Accumulate a total of 150 Miles of Highway & City Driving following steps outlines from one to four.

  • Return to Joe’s Drive Thru Smog Check Star Station for your Smog Check Inspection.

What Is the Purpose of a Drive Cycle?

When a vehicle has an emissions system problem, it almost always triggers a MIL Check Engine or Service Engine Soon Light. This signals that an emission system problem and fault code has been recorded in the powertrain control module (PCM). The problem indicated by the fault code must now be accurately diagnosed and repaired. 

After the proper repair has been completed and the fault code cleared, the PCM will run a series of self-tests to determine whether or not the repair actually corrected the problem and if the various emissions systems are running properly. If they are, they can now properly minimize the emissions released into the atmosphere from the vehicle's operation.

This process was designed to prevent a vehicle from slipping through an emissions test with a known problem. Until 1996, a common tactic was to turn off the Check Engine Light by clearing the code just before an emissions test, without performing the proper repair. The Drive Cycle and Emissions Readiness Monitors have, for the most part, stopped this unethical tactic.

Effective July 1, 2019, model year 2010 and newer vehicles with an OBD II Permanent Diagnostic Trouble Code (PDTC) stored in the vehicles computer memory will fail the BAR-OIS Smog Check, even if the MIL is not commanded on. This check augments the existing inspection requirements and failure criteria for OBD-equipped vehicles. Vehicles are excused from the PDTC requirements once the vehicle has traveled at least 200 miles and completed at least 15 warm-up cycles since the last time Diagnostic Trouble Codes (DTCs) were cleared. PDTCs are the same as regular DTCs but are stored in a more permanent portion of the vehicles computer memory. They cannot be erased by clearing the DTCs with a scan tool or by disconnecting the battery. PDTCs can only be cleared by the OBD II system once it has verified that any defects are no longer present. When a vehicle fails for having a PDTC, the fault code will appear on the Vehicle Inspection Report (VIR) under the category Permanent Fault Codes.

Joe’s Drive Thru Smog Check Star Station

10909 Burbank Blvd

North Hollywood, Ca 91601

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