ok, my car just failed the emissions test here in Texas. here's specifically what failed; catalyst: not ready
evap: not ready
2nd sys: not ready
o2 sens: not ready

I understand the one on the o2 sensor, but what about the other ones? on saturday, I changed plugs/wires, but that was it. I closed the cut-outs and put about 140 miles on the car after that. Have any of you guys seen this before and is it something I can fix without going to the dealer.

 

Did you clear any codes or replace/disconnect the battery recently? If you did you have to wait for a whiile or do a "Drive Cycle". The drive cycle is in the thread:
http://forums.corvetteforum.com/c5-t...eset-take.html

 

Read and post your DTCs. If you cleared the DTCs or disconnected the battery,,,it will make all that stuff NOYT READY until you complete the GM driving cycle. That takes a while.




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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thanks guys, I will try this. the only codes i have cleared are for the tpms [rf codes] the car should be completely cooled down by now, I have been doing the duplicolor treatment on a set of track wheels[ turned out nice btw]. I will let you know if anything changes.

thanks again.

 

So I have to do this procedure if I replace my battery??

 

Yes,

If you don't you won't pass the testing.

I had to do the above procedure to get my car to show a pass on the Handheld tester I have prior to taking it in for emissions testing after removing the battery to inspect the car prior to buying it.

Follow the above procedure and it will pass unless there is an actual issue with the emission control system.

 

Have you done any mods that effect emissions? If so send me a pm and I wil direct you toa permanent and immediate fix.

 

IF,,,,,,,,,,you need to pass an EMISSIONS TEST soon after the battery replacement, yes yu will.

If not, dont worry about it. It will pass on its own and will not be an issue.

BC

 

Exactly. Assuming the car has properly functioning emissions equipment, the self -test cycle will complete on it's own. It just might take more then a day for you to meet all those checks on your own if you have cleared DTCs or had the power disconnected today.
A shop with a Tech-2 can verify these system checks for you before you take it in for emissions testing.

 

OK...change the battery, drive for a few days, car should be back to normal as it was prior to the battery swap. Got it.

 

The "cheapy" OBD scanners like Actrons will show you the status of these I/M tests, you CAN'T see them via the DIC diagnostics. Many states that test for it allow 1 of these I/M's to fail and you still will pass. 2 or more and you will fail.

 

One thing I learned recently about the EVAP being "NOT READY".

The EVAP is something that monitors the evaporated gas in the fuel tank, and re-circulates the fumes (something like that). Anyways.... you must have your gas tank under 3/4 full for this system to even start to test itself.

I had my battery disconnected a few months ago. I also put on coil overs. I was keeping my gas tank full every time I drove it because I was dialing in my coil overs. I failed my emission test. I drove the car until it got under 1/2 full, and I went back and passed. Then I went and filled it up and continued dialing in my coil overs...

Toque

 

Evap not ready got me today and I guess having to put a new battery in a month ago doesn't help either.

 

EVAP got me last time too. I had my battery disconnected and I only failed for EVAP. Turns out that you need to run your fuel tank down to about 3/4 or less for the car to run the EVAP test. Do that and you should be fine. I ran my car down to 1/2 full and I passed.

Toque

 

Just ran it down to til the reserve light came on and no dice. May just get a tune and get rid of the catalyst not ready to solve the problem, but I'll try and put some more miles on if 1st.

 

been scanning the web to try and get my 2000 silouette ready and keep coming back to the procedure above that I have done 4 times now and still not ready.

have 250 miles in the car since failing the first time

this is sickening

 

I screwed around since August trying to get my V to pass smog.

If you look it up, the Evap and Cat Eff tests are the most difficult, and in fact, there are waivers for some cars as these tests will never initiate!

The "smog" expert at the dealer was pissed because when GM was developing TECH II, it was suggested that these tests could be "forced" by TECH II but was rejected.

Pretty bad when the dealer throws up his hands!

Good luck finding a spot in Los Angeles,at any time before midnight, to go 55 for 5 minutes then decelerate to less then 20 without touching the brake or clutch.

 

Being new to the C5, coming from my C4, which in Illinois was too old to test... this Driving Cycle Test procedure is !@*&#$^!*&$^%!@#^$%!@&!!!

Not much useful to add, except, good luck.

 

Having just failed emission, I thought this tread worth bring back into view.

 

I'd have to double check the C5, but most engine management systems will not perform an EVAP test (to set the readiness flag) unless the fuel level is between 1/4 and 3/4 of a tank.