Does clearing a code put the PCM in a mode where it won't allow an emissions test?

I had recently cleared a code that popped up due to my new LTs and I've only driven for a few trips since, maybe about 100 miles total. I took my car in to a local garage for the annual state inspection this morning and they failed it on emissions because their computer says it's "not ready for test".

Any way to view the status of this with an X-Cal 3?

 

You most likely have not completed the OBD 2 Readiness tests....Drive some more cycles....Ex. Turn vehicle on, drive 10 miles, shut vehicle off=one cycle

 

Do your LTs have all four O2 sensors installed? Do you have cats? If your tuner turned off the rear O2 sesors (very easy to do via the software), then you will NEVER get an ODBII ready.

 

All 4 O2s connected, catted H-pipe.

Guess I need to call the shop that tuned it to find out if the rears are turned off.

Thanks for the info.

 

What's the story with LT's and offroad pipes going for emissions testing? Would MIL Eliminators allow the rear O2s to be left on without causing an error code or emissions failure?

Obviously, this wouldn't pass a "sniffer" test, but for the OBDII test would this suffice?

 

MIL Eliminators should work. The ECU THINKS everything is ok and the rear O2 sensors are left on. The only issue is if the tech actually looks under the car to verify all the parts are in place and working.

 

Thanks! It sucks living in one of the 7 counties in Ohio requiring emissions testing... All because of the bad air around Cleveland due to industry...

 

In Illinois you can pass with one monitor in "not ready status"
I plan on passing my test with the rear o2's off.


Certain things need to be done before a monitors are set. Like cruising speed for a period of time, some stop and go, warm engine driving, cold engine driving, etc.
100 miles may not have been enough. Try taking a 20 minute cruise on the expressway.

 

Here's an update. Stopped in the shop that tuned my car and he confirmed that the rears were off. He gave me a new tune with them turned on that I can run until I get it inspected, then I can put the other tune back in. Problem is, even with babying the car and letting it idle for a bit before driving, it's throwing codes.

If I clear the code does that reset the "ready for test"?

If it does, that's a catch 22. I have to drive the car so many cycles to get the "ready for test", but by driving it, it throws codes.

 

That seems to be pretty standard practice. Not sure why, but it is.


This means that your tune is NOT up to snuff. If the computer is throwing codes, then the tune has to be adjusted until there are no codes thrown. I think you would be well served getting a set of MIL eliminators for the rear O2 sensors, since they will effectively tell the computer "all is good back here," and eliminate one potential source of issues completely. If you do that, and the car is STILL throwing codes, then you have a serious tune issue. If your "emissions" tune is simply your standard tune with the rear sensors turned on, then the MIL elims should cure all.

 

Well, looks like I have the same problem now. Went in for emissions testing today, and failed on 4-5 "not ready"s. I cleared a CEL (some emissions catalyst thing) just before heading to the inspection place, so I don't know if that causes those monitors to reset to the "not ready" state. Anyone know about that? Anyway, I guess I'll drive around for a half tank of gas or so and see if the CEL comes on again. If not, back to the emissions analyizer for round 2. I really thought I had this issue resolved.

CR, I might need to work on our tune again....

 

I bought a set of the MIL eliminators from Brenspeed

http://www.brenspeed.com/mustang_2005/midpipes.html (scroll down)

and they did the trick. Kind of annoying since there's really no need for these other than to get the car to pass emissions, but that's our government making life easier for us.

 

I think if you clear the CEL, it resets the sensor and could cause the not ready readings.

 

Keystone, yeah, I already installed the MIL elims when I installed the LT headers months ago. I was hoping they would take care of all my emissions testing issues.

So hopefully theedge67 is right, and when I cleared the CEL, it reset the monitors to 'not ready'. I cleared that code 3 miles before I went in for the inspection....oops.

 

Oh right. You're going to have to dive it to get the computer to complete its self-check. Not sure exactly how many miles - or as some have said, cycles - that takes. Once you have some miles/cycles on it with no codes, the test station will plug into the OBDII port, your computer will report all is well, and you'll get your sticker.

 

Just wanted to follow up on how things went when I took the car back for the second run at emissions testing. After driving about 100 miles, I took it back to the same place to see if the 4 "not ready" sensors were now ready. I didn't have a new CEL so I was hopeful. He plugged in the emissions analyzer, and ALL monitors were "ready", so I PASSED. Whew!

So, with all of the mods in my sig, it is possible to pass emissions testing, w/o having to remove anything or retune. And the 2nd thing I learned, deleting a CEL, DOES reset several monitors to "not ready", which takes 50-100 miles to make them "ready'.

 

mine just passed the "sniffer test in GA without cats, mac longtubes & pro-chamber 321 rwhp. Of course the guy didnt "look" at it so you have to have someone who agrees not to "look" but as far as the sniffer it was all good.