jochumr

Reason: This vehicle failed the MIL/Check Engine Light due to failure to successfully complete all OBC self tests.

What is this?

And how do i fix it?

dougbfresh

Which tests were NOT READY? Have you had the battery disconnected or reset any codes before you went to the test?

RonR80

and also your car has to be in the operating temperature . A cold engine will not pass . Reset the codes and warm it up good and go back . I'm assuming your car has no mods on it . Ron

dgrant3830

I wouldn't necessarily reset the codes. This will force a number of heat up cycles to pass before the emissions will pass. Pull your codes though using the DIC and see what's up. It will tell you what's wrong.

dougbfresh

This is bad advice-resetting ANY code(s) will reset ALL the I/M monitors too-some of these monitors take a while to run (i.e. the EVAp test won't run till the gas tank is about 1/2 empty). Generally takes a few days of normal driving to run all the tests on it's own. There is a DRIVE CYCLE test where you can get the test to run but it's almost impossible to drive the car that way unless your on a treadmill.

dgrant3830

I agree completely

Bill Curlee

There are numerous EVENTS that can cause your PCM to be I/M self test NOT READY.

Check the following:

- READ YOUR DTCs! Report ALL the DTCs that you see and be sure to include the H or C suffix! FIX the problem causing any P-XXXX DTCs

- Battery condition!!! Have your battery fully charged and go have it tested. If you battery has poor cold cranking capability, it will allow the B+ (12VDC buss) to drop low (under voltage) during cranking. If the B+ voltages drops below the module low voltage cut off, (like the PCM) it will be just like resetting a code or disconnecting the battery. You will have to do all the drive cycles to get it ready.

- DO NOT clear any DTCs before you have the emissions test!

- DO NOT disconnect the battery before you have the emissions test!

- You can use a OBDII scanner to monitor your I/M -Test/Flags. The scanner will tell you if any of the emission flags are NOT READY. That way, you won’t waste your time at the emissions stations. AUTOZONE has a FREE Scanner policy and all the ones that I have seen them use will monitor emissions status!

Hope this helps!


BC

Bill Curlee

You can try to follow this test and force the DRIVE CYCLE to be completed. Make SURE that you follow ALL the steps (if you can! )




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:

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.

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.

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.

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.

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.

Accelerate. Accelerate at 3/4 throttle until 88-96 km/hr (55-60mph). This will perform the same diagnostics as in step 3.

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.

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

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jochumr

Follow up .... I screwed up and hit the rest the other day ... TCS throws the C1214 code any time it rains .. HVAC threw a code (cant remember the numer) but it happens when anybody shuts the passenger vents completely off and then plays with the console passenger dial. The damper is out of sync. And the SCM threw a code (again wasnt thinking and cleared it.)

Bill thanks for the explaination ... anyone in Calf will need to paste that one to the visor .. next year CA SMOG drops the sniffer test and relys completely on the OBC ....that should be interesting!!!(''AB 2289 - New Smog Check Law- Set to begin January 01, 2013; Model year 2000 and newer vehicles will no longer require the tailpipe emissions test portion of the smog check process. AB 2289 will require late model vehicles be administered the smog check's visual and functional tests only.... ''search for crazyE complete post)


Thanks everyone saved me a trip to the dealer ($$)

tblu92

In Calif you used to be allowed to have 2 of the readiness tests set to NOT READY ---This was changed to only 1 a few years sgo---- So you can have 1 not ready in your readiness monitor system-----However-- you can NEVER have any check engine lights---
Too bad you reset it and cleared all the codes---Now you will have to go thru the entire readiness system process--It is a true PITA----You usually to get the last few set have to let the car go completely dead cold like in the morinng at least 2-4 times to get them all to set----
I would borrow a scanner and you can watch the progress of the tests in real time without clearing the codes or resetting the monitors----And it will tell you witch ones are hanging you up and how many are left---When you get to just one left you are good to go--
Read carfefully "not completely" mean they are notset yet but also some test read
"not supported" which means your car doesn't have to have these set to "complete"
( old guys like me with bad eyes make mistakes on these all the time !!)
You can also go to Autozone ad they can read the readines test progress for you--and tell you how many are left to complete But be CAREFUL and be sure to tell them to NOT clear the codes !!!!!!! or rest the monitors or you'll have yo start all over again !

jochumr

Thanks!

dougbfresh

Most states will not FAIL you for non emission codes pending in the computer. The codes you had should not have failed you (the 1214 I think triggers the AH/TC light not the CEL. for example). Your reset is what shot you in the foot.

Ikester

Just wanted to share my feedback with what GM states. I recently failed inspection for

• Evaporation Not Ready
• O2 Sensor Not Ready
• Air System Not Ready

My car is hardly driven in Winter (on CTEK charger) so I tried the GM procedure as Bill posted. Here are my findings:

1. AC will not power on. I assume because the weather was kind of chilly and the HVAC thinks its not cold enough for it. The AC light will only flash then its off. I put on the windshield defroster on high but still did not turn on AC/

2. For deceleration after 55mph, the car will only coast down to about 30mph on 6th gear. The only way to go down to 20mph is to press the clutch which will cancel the test anyway. In addition, this is dangerous to do on a public highway even on the right lane. People will eventually come up behind you and have to hit the brakes. I even had my hazard flashers on but it still not safe.

After returning to the inspection station, issues still remained. So for now I will drive the car every day this week and come back for another try.

Bill Curlee

Ikester

During your next test,, do it in a lower gear (say fourth) and see if it will Decelerate down to that required speed.

If your car is cold but above 32, the AC should still come on. If the cold temps caused the R134 pressure to drop lower than the LOW SPEC, it wont let the clutch operate. After the engine is fully warm see if it will come on. If it doesn't, have the R134 checked and see if the system is still fully pressurized to the correct levels.

Bill

Ikester

Thanks Bill good point about AC, I have never recharged the AC refrigerant since I bought the car (in 2004) so maybe it is low. And I doubt the first owner has done it... Its due for a checkup

Ikester

Update: Drove the car 4 times this week with less than 1/2 tank of gas. By driving I mean went from cold start to operating temps. 28 miles a day round trip to work. That set the EVAP test to ready and I passed.

NJ DMV allows 2 not ready

Big_George_S

Great Post Bill, I'm printing this out and keeping it in my book.

Also it is good to have a Corvette friendly smog shop. I happen to have one. PM me and I'll share. California was ground zero for hot rods and modifications. Now they will try to put you away if you even look under the hood of your car. Remember to Vote!!!! Oh yea and they want more of our tax $$ for the train to no where, or what is now being called the Moonbeam Express. Only in the Republic of CA

jochumr

Finally got the PASS today!! Seems the EVAP was the culprit, driving around and less then half a tank of gas later it reset.

Whats funny is the C1214 popped up during the test and it didnt phase the tech or the test!!

Bill Curlee

Cause its not a PCM Emissions code. Only PXXXX DTCs will fail you.

BC

dougbfresh

That's what I said. Only the generic emission codes, I/M monitor tests are what they are looking for. Get a cheap Actron scanner at Autozone/Sears for the I/M monitors and you'll alway know BEFORE any of your cars go if they will pass and you can get codes out of any others cars you might have.