HELP: Emission-testing advice, needed

[97tbird]

Hi all,

I just moved to Harnett County, North Carolina from TN, and now I have to have emissions inspections done in order to get NC plates, etc...

My car has never had emmisions tested before, and I don't know if I should "prepare" the car for this???

As far as I know, it never had any such emission-related problems. well-maintained: no smoking/real oil burning. Made the 6-7 hr interstate trip from TN to NC fine.

The car is a 1997 T-bird with 98k miles, 4.6L mod.
Using Shell v-power right now(pings a bit with lower oct.)
Has M1-5w/40 in right now.
Had 1-time Arx treatment about 10k ago.

Spark plugs(plat)/wires(Motorcraft) are about 15k miles old. Coil packs are original ones. Still has original O2-sensors, orig. cat.coverter, and orig. exhaust.

Do I need to do anything to make sure that my car will pass emmisions? if Yes, what? What do they really test?

Your advice is very much appreciated.
Thanks.

[ August 03, 2004, 01:41 PM: Message edited by: 97tbird ]

 

[Gary Allan]

Don't fret over this. The standards get more relaxed as the car ages (typically). You're OBDII ..which means if you had a serious engine condtion ..you would probably get a code. Your O2 sensors would read "lazy" or something like that.

Do they actually do a sniffer test ...on a dyno maybe? Many states to start testing only use a scanner for the OBDII vehicles (Md. and PA). If NO CODES are present ..it gets the badge (or the stamp on the reciept so you can get your tags).

If it is an actual sniffer test, I'd recommend changing the oil before the test if it's anywhere close to being due. If the throttle body has never been cleaned ..do it ..but not right before the test ..the residuals being washed down into the combustion chamber may take a few miles to burn off.

 

[Virtuoso]

At about 100k miles, it might be time to replace your O2's (they will affect emissions), even if they're not throwing a code. I'd bet they are already slow.

 

[Dan4510]

Also,

Make sure the car has been run and up to temp before the test. If not, the converters might not have come on line and the computer might not be in closed loop opertion that helps limit emissions.

Never do an emissions test with a cold car, even a brand new one. If nothing else it encourages them to keep hands off from the temp if nothing else.

Dan

 

[seotaji]

quote:

---

Do they actually do a sniffer test

---

only on cars without OBDII.

they usually hook it up to a scanner and trust what it says.

looks for CO and NO.

if you are really afraid that your car will not pass, just buy a bottle of that "guaranteed to pass stuff" usually in a green bottle - it's just alcohol.

 

[darryld13]

Be sure to take a look into what happens should you fail the emissions test. In some areas, if you prove that you spent, say $500 at a repair shop attempting to correct the emissions failure, the state will sometimes provide a waiver. The dollar amount is usually conveniently approximately the cost of a tune up at a garage. If that is the case, I would think twice before investing $$ on big ticket items before failing.

[ August 03, 2004, 05:20 PM: Message edited by: darryld13 ]

 

[darryld13]

Check Tennesee's OBD II web page - seems to indicate that if you don't have a Check Engine light, you chances are good that you will pass the emissions tests.

[ August 03, 2004, 05:26 PM: Message edited by: darryld13 ]

 

[97tbird]

Thanks for all the help/replies.

I think I'll do what you guys have suggested before the test;

I found the exh.gas emission-limits for NC online:
[CO] max: 1.2
[HC] max: 220
wonder what units those are..ppm or soemthing?

So, Here's what they basically do( per NC_DMV website):

They use a DMV approved "emissions gas analyzer" to measure the CO and HC levels in exhaust gas(idle), check OBD-II emission codes, and insert a probe in to the tail pipe to make sure everything's intact.
No mention of measuring NOx levels...(?)

Now some more (?)s:
The fact that I'm running 93 oct. in my car(pings with lower oct; at least used to): how does the oct. level of the gas affect the emissions? (+) or (-) ?

is running fuel inj.cleaner (Techron/FP) before the test advisable?

My oil (M-1 5/40) has only about 3k on it, so i don't think I have to change it(???)(
it does have a 7 -hour interstate trip on it, though)

If failed: I could not find the upper limit of how much you have to spend getting your emission-problems corrected before they let you drive it anyway in NC; several sources say there should be one. Does anybody from NC know what this limit is?(searched on DMV website to no avail)

It's unbelievable: they also charge an extra 10 bucks to check cars with window-tinting for correct amount of light passing through! My bird has a factory tint!!!

Thanks a lot, again.

[ August 03, 2004, 06:13 PM: Message edited by: 97tbird ]

 

[brianl703]

quote:

---

Originally posted by darryld13:
Check Tennesee's OBD II web page - seems to indicate that if you don't have a Check Engine light, you chances are good that you will pass the emissions tests.

---

For those states that do OBD II testing, they require that the readiness tests be complete. So someone who thinks that they can get the code cleared and the light turned off and then take it and get it passed is quite mistaken, because clearing the code makes the readiness tests incomplete.

Once the readiness tests have run and completed, whatever problem caused the light to be on in the first place will have caused it to be on again.

That being said, some states that do OBD-II testing will allow up to 2 readiness tests to be incomplete and they will still pass the vehicle.

So if you have the OBD-II information for your vehicle, you may be able to clear the code, then drive the vehicle in a manner that will not allow the readiness test for whatever code it was to run, while still allowing the others to complete.

Then take it in for testing.

This really would work well with those pesky "catalyst efficiency below threshold" codes, because that catalyst test is usually the LAST one to complete.

 

[Gary Allan]

quote:

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Once the readiness tests have run and completed

---

You've got to enlighten me here. Just what are you saying? What I've sorta patched together in my mind is that you're saying that IF you had a MIL/CEL code lit ..and clear it (only doable with a scanner typically)...you won't pass since, as you indicated, the cause will still be present.

This would naturally assume that anyone who had a scan tool ...actually saw the light ...read the code ..knew exactly the fault ...yet drove that way anyway and even tried to get the thing a badge/tag by trying to skate on the emissions test.

Is that essentially it??


I'm just asking since I cleaned my son's throttle body on his beater Neon, while running, and it got a code (multiple misfires) .....grabbed the scan tool ..noted the code ..cleared the code ...no problem. This thing certainly passes OBDII requirments.

 

[brianl703]

The short answer: Simply drive your son's neon (fully warmed up) for about 10 miles at highway speeds (not exceeding 65MPH) with a couple of idling stops. This should allow all of the readiness tests to complete.

The long answer:

The readiness tests are tests that the OBD-II system runs to test all of the components. These tests are run under certain driving conditions automatically.

Readiness tests include the following:

Catalyst
Comprehensive Component
Misfire
EGR
Evaporative Emissions

If a readiness test fails--twice, in two separate driving cycles--the light comes on[1]. If it fails only once, the light does not come on, but the code will show up as a "pending" code with a scantool. If it once again passes, the "pending" code goes away.

When you clear the codes, the readiness tests will show up on the scantool as incomplete, until such time as they have had a chance to run again. When they run again, any fault that is still present will cause one of the tests to fail, you will have a pending code in memory, and if it fails the test on the next driving cycle, the check engine light will turn on. If the test passes again, the the light will turn off. (It may take more than one test pass to turn the light off).

As I mentioned, in states that do OBD-II testing, if the readiness tests aren't completed, they may fail the vehicle or more likely, tell you to come back again later. But some states allow up to two readiness tests to be incomplete and will still pass the vehicle.

[1] Ford uses a weighted moving average which means it can take more than two failures during two driving cycles to turn the light on, but this is disabled for the two driving cycles immediately after clearing the codes so any failures will make the light turn on sooner--much better for the mechanic who cleared the codes, fixed the problem, and is taking it for a test drive to verify that the problem is indeed fixed.

[ August 04, 2004, 10:19 AM: Message edited by: brianl703 ]

 

[Jimbo]

quote:

---

Originally posted by 97tbird:


I found the exh.gas emission-limits for NC online:
[CO] max: 1.2
[HC] max: 220
wonder what units those are..ppm or soemthing?

So, Here's what they basically do( per NC_DMV website):

They use a DMV approved "emissions gas analyzer" to measure the CO and HC levels in exhaust gas(idle), check OBD-II emission codes, and insert a probe in to the tail pipe to make sure everything's intact.
No mention of measuring NOx levels...(?)

Now some more (?)s:
The fact that I'm running 93 oct. in my car(pings with lower oct; at least used to): how does the oct. level of the gas affect the emissions? (+) or (-) ?

is running fuel inj.cleaner (Techron/FP) before the test advisable?

---

CO is measured in percent and HC is ppm. It sounds like an idle test, so pinging under load is not an issue. I would use the lowest octane fuel possible, because it tends to burn faster, a plus at idle speeds. Techron will probably fix your ping problem anyway, as it has for my Fords. Check your timing. Advanced timing will cause increased CO and HC as well as pinging. Mom's Dodge just failed on HC because of over-advanced timing.

Dan stated the single most important factor. Bring it in hot, preferably right after a highway run of at least ten miles. The cats and O2 sensors have to be hot to work.

 

[Jack from Charlotte]

97

I wouldn't be overly concerned about the inspection. I've been doing it here in Charlotte for 12+ years with no problem. My wife's '90 Jag and one of my previous Taurus each had about 150,000 miles and they always passed. Since your plugs are fairly new and if you've got no "Check Engine" lights coming on, there's no reason to think you'll have any trouble. Like the others have said, run it and get it warmed up. Also, you may want to be the first one there in the morning. Sometimes here in Charlotte, there are 3 cars ahead of you and I think you'd rather have the engine warm, so get there first.

Just check, see if you've got a tail light or brake bulb out or some such. I've had to replace them in order to pass and drive back over there.

Yea. Too bad on the window check... $10. Makes the total cost of inspection $40.

One other thing, it used to be $200. If you show evidence of having spent $200 to repair a failed emission something or other, they'd pass you.