2001 Eldo won't pass emission. Help!

[Bill Caddyshack]

Trying to pass Georgia emission to get a new tag.

All the codes are clear. Car runs great!

BUT

It will not pass "clearance". When I get to the end of the inspection, it will not pass. Inspection station tells me to "Drive it one hundred miles" and it will "clear out". Brought it back, several more drives.

Does not work. Been to several garages who have "The GM Computer" but still no answer. The car's personal computer checks out fine. Mechanics tell me they have never seen this problem. Northstar mechanics mystified.

Sure would appreciate your help!!! Bill

[V63]

If 'all codes' are clear, then what is there to 'clear out'?

HOWEVER

If the battery is disconnected, there is a drive period of time where the computer 'relearns'. The inspection station is aware of this relearning sequence as many people attempt to erase codes by disconnecting battery. Your 'drive' sequence will require a specific formula of drive speeds and duration ect outlined in the shop manual.

[Dave Shepherd]

If codes sere cleared or the battery disconnected​, the emissions monitors are off line til the appropriate drive cycle wakes them up, there is a specific procedure that can be googled. Some vehicles only require maybe 50 miles, I have seen up to 125 required.

[Bill Caddyshack]

If codes sere cleared or the battery disconnected​, the emissions monitors are off line til the appropriate drive cycle wakes them up, there is a specific procedure that can be googled. Some vehicles only require maybe 50 miles, I have seen up to 125 required.

The Problem is trying to pass "Readiness."  Passes all the qualifications until the last check.

Yeah, did all that. Ran for 150 miles. No good. Ran it again, no joy, have over 500 miles trying to get it to work. Tried driving around town, and also on the expressway. Car runs beautifully. NO CODES being thrown.

Possible problem. Local mechanic said my positive cable is flaky. He thinks a weak battery can be the problem. Battery is good, but the positive cable is  cobbled together.

Now I am passed tag expiration.

[Jeff Wilk]

Just had this problem on a used Honda for my Son at College that had sat for a few months with no battery. The drive cycles are not just about mileage. Each car is different and require some mystery combination of a certain number of miles in each of several driving conditions.....highway and city and rush hour traffic and idling....etc. There is an indicator in the Honda (basically a blinking sequence of the engine light) that tells you when these settings for emissions have been relearned by the inboard computer. Once we saw that the cycles were done we went back to inspection and the car passed inspection without a problem.

Jeff

[J. Gomez]

The Problem is trying to pass "Readiness."  Passes all the qualifications until the last check.

Yeah, did all that. Ran for 150 miles. No good. Ran it again, no joy, have over 500 miles trying to get it to work. Tried driving around town, and also on the expressway. Car runs beautifully. NO CODES being thrown.

Possible problem. Local mechanic said my positive cable is flaky. He thinks a weak battery can be the problem. Battery is good, but the positive cable is  cobbled together.

Now I am passed tag expiration.

Bill,

Not sure if these steps would be of any help in your case; http://www.obdii.com/drivecycle.html   

Also if you Google your specific situation there may be other details that could be available in your case. Some of the hits from Google also indicates a repair may have been done after a check engine was trigger and reset and/or a battery was disconnected but the driving cycle not yet completed. 

Maybe replacing the battery cables may do the trick.

Good luck..!

[Bill Caddyshack]

Bill,

Not sure if these steps would be of any help in your case; http://www.obdii.com/drivecycle.html   

Also if you Google your specific situation there may be other details that could be available in your case. Some of the hits from Google also indicates a repair may have been done after a check engine was trigger and reset and/or a battery was disconnected but the driving cycle not yet completed. 

Maybe replacing the battery cables may do the trick.

Good luck..!

Will try this. Not sure what to do because my license tag is expired. Local cops have dash cameras that KNOW immediately and automatically that the tag is expired., so how to drive the car after having replaced the starter cable?

[Glen]

When I bought my 03 S10 pickup I checked it with my scan tool and found the emissions monitor had not run.  I checked the shop manual and it said it would run when the tank was between ¾ and ¼ tank of fuel and a few other conditions. 
I kept checking and the monitor never ran. 
I finally figured out that another problem was causing this one.  The problem was sometimes when trying to start the engine the battery voltage would drop to about 4 volts.  This low voltage was the equivalent to disconnection the battery.  When that happened all the monitors would reset and have ot run again.  Emissions was the last to run. 
When I changed the battery, and removed a battery connection the previous owner put on I soon found the emissions monitor had run and all was well. 
So if you are having battery or battery cable problems this may be the cause of your problem

[Glen]

This might help also

from: http://www.obdii.com/drivecycle.html

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

[Bill Caddyshack]

I really do appreciate your kind assistance. Looks like the answer is to replace the battery cable. This is hard to do as it also goes to the starter - which is under the intake manifold - BUT

1. Replace the positive battery cable - try
2. Run the "drive cycle"
3. if not above, replace the battery - which is only about 6 months old. But Costco will replace it as still within warranty. (Interstate Battery)

Thanks

[Dave Shepherd]

Any time you disconnect the battery the drive cycle must start from scratch, unfortunately.

[Bill Caddyshack]

Any time you disconnect the battery the drive cycle must start from scratch, unfortunately.

Dave, we'll start with the drive cycle. Thanks.

[Bill Caddyshack]

Found the answer. Since I am over 65 and my car is older than ten years, State of Georgia allows a senior waiver. I don't even have to pass the emission inspection!

YAY!