How do I pass inspection in Texas with a check engine light (clearing codes)?

This is more of a point to make. This person has a car which will not pass emissions testing and in the big picture their pollution along with likely thousands of others in the same state are a drop in the bucket compared to the biggest fuel consumers/polluters in the same state.

That is the number of aircraft over that same state of TX. I have an app on my phone that shows every aircraft (Piper Cub to 747 to Airbus A380 to C5 Galaxy, private,commercial, military) that is in the air in real time. It shows the actual plane, alt. speed, where from, where to, etc.

If one viewed that I doubt that anyone would even want to leave the ground and would wonder how in the world air to air collisions are not happening every minute. It even shows when one declares an emergency. No wonder ATCs are stressed.
It resembles a roomful of millions of Lego blocks except the color of the planes signify altitude.

Think of the pollution and amount of fuel being used just over one state. A single 747 has a fuel capacity of approx. 200 tons. A single small commuter plane will burn more fuel/create more pollution exiting the state than the OP would in a year.

Also, TX has 254 counties. Only 17 require emissions testing. Sister lives in the Fort Worth area so she is familiar with it. No idea how they will stop pollution from above or at the county lines…

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A source linked below says that industry, power, and transportation are by far the largest contributors to air pollution. It’s not a simple estimate since there are a number of pollutants to consider. See Table 1.3 in the paper. Still, those three tick a lot of the boxes in the table.

If the state’s emission testing folks who admin the program adopted the attitude of doing everything possible to help the diy’er car owner get the car running correctly based on clear and unambiguous recommendations, that would go a long way towards solving the emissions paradox we have now. That’s far from the current situation, at least in Calif. For example if you don’t pass the first attempt here, you’re registration is likely to expire before you can try again,.
And you won’t be able to drive your car to the testing station for the 2nd test. Instead you’ll have to go to the DMV first to get the registration extended (for a big fee), which you can’t do fee or no fee b/c your car isn’t registered to drive to the DMV. Common sense says to provide an automatic 3 month registration extension if the first test doesn’t pass. I don’t see that happening anytime soon.

There are (in theory) $$ limits here to what can be charged for emissions repairs before the vehicle automatically passes, but trying to figure out what those are and whether they are applicable in any particular case from reading the DMV website is nearly impossible. At least from my experience. And how does an automatic pass help make the air clean?

Most car owners want their car to run correctly, as designed by the manufacturer. So what’s needed are actual people at the DMV who provide actual help on getting the car to pass the emissions test. Instead what we have is mostly impossible to understand bureaucratic verbage. Understandable help for the diyer is not available at this time. Like with any gov’t policy, there are winners and losers. The car owner unfortunately is in the second group.

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The DMV instructions seem clear;

I don’t think CA residents want to pay for hundreds of skilled technicians to assist vehicle owners in diagnosing and repairing junk vehicles, a system like this will get out of control.

Ride share has replaced taxi service, there is also bus and bicycle. I have my vehicles tested 30 to 45 days before expiration.

Read the link tester sent you. The inspection station will not care how recently the codes were cleared as long as the check engine light is off and all the readiness monitors have been reset by a drive cycle.

My state (NY) will pass you if you only have one system not ready to read. Two, if it is a 1996. I have no Idea what Texas law is.

If you don’t live at old address, how will you get new tabs? Or proof of insurance?

That’s known as “planning ahead” in my book

That way, if you DO fail, you might actually have enough time to diagnose and fix it before the registration expires

Over here in California, that one allowable incomplete readiness monitor can NOT be the catalyst monitor, afaik

And it’s gotten even stricter with newer cars

Now there are “permanent trouble codes” which remain in memory and can’t be cleared until x number of good drive cycles have occurred. It’s a LOT of driving involved. No such thing as one good trip to get the car ready for smog

It’s getting harder to clear the codes and show up at that sweet spot moment in time to pass, knowing the mil will illuminate soon afterwards

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On older vehicles even disconnecting the battery will clear the codes and reset everything. Newer ones have a separate code list that can’t be cleared, which reveals past codes.

Nahh. Tailpipe emissions testing just looks at what is coming out of the tailpipe at the test station under minimal load. There’s no way to simulate the actual driving pattern of each customer or what is happening when the car is driving at 60mph.

A tailpipe test won’t show that your car was running at 2.5% CO for 25 minutes before you got there because your thermostat is stuck open and the engine is cold. A tailpipe test won’t show elevated HC caused by an intermittent arcing plug wire because there’s almost no load on the engine at the test station. A tailpipe test won’t show a sticking EGR valve if it happens to be working at the test station. OBD2 shows a history of events and long term memory of what’s going on.

Tailpipe testing does nothing to address evaporative emissions.


The tabs (tags) can last 2 years. Proof of insurance can be printed online. 2 years isbl enough time for me to get settled in the new state and figure something out.

Tailpipe testing is required in Calif for OBD I vehicles & before, but it isn’t done at idle. Instead they do it on a car-treadmill, so the car is actually driving down a simulated road, and there is a corresponding load on the engine. Emission testing is not required in Calif for vehicles vintages prior to mid-70’s.

Many CA residents would be offended by your comment about driving “junk” vehicles . Do you think CA residents would rather pay the state to hire a group of technician to provide free skilled help, or pay the Smog Check businesses instead? The BAR-Auto Shop Locator looks like an advertisement to me. State sponsored businesses. I can see why the businesses like that idea, who wouldn’t like to have have guaranteed customers who the state says must use their service.

It’s sort of like when a local agency complains about some minor issue, a 2 x 4 isn’t properly placed, something like that. If the owner asks which 2 x 4 it is they are complaining about, the response will almost certainly be “We don’t have to tell you. It’s up to you to know which one is not in compliance!” … sigh …

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It’s not an advertisement, imo

And nobody says you “must use their service”

Tell them to get used to it, I did and my car is not in a state of disrepair. People who buy new cars look down on those who drive the trade-ins.

Since about 98% of vehicle owners do not fail emission tests, these people would not want to pay for a welfare program to help make old cars roadworthy. California already has a support program to assist those who earn less than 225% of the poverty level.

Yesterday my car was drenched in smoke from the vehicle in front of me while accelerating from a traffic light, I am in fear of other motorists reporting my car for smoking. These junk cars can be a burden on all of us.

Is that even a thing? Do they have a hotline for the junk car tattlers in CA or something?

There is a “report smoking vehicles” hotline in Nevada, after several complaints the vehicle owner must report to the DMV emission control department for inspection. Years ago, I received a “smoking vehicle” warning letter from the DMV, I stopped driving that import a year later.

Wow. Sounds like a great use of tax dollars. Seems like the emissions inspections would catch the smoking vehicles at some point anyway.

Eh. The worst emissions are the ones you can’t see.

Dyno testing can’t be done on 4WD or AWD vehicles. These represent an increasing number of cars on the road. 66% at my house, and just driving around town I would estimate at least a third of cars on the road. Traction control and ABS also interfere with dyno testing. It simply is just not as comprehensive a test as the OBD system. And again, tailpipe testing doesn’t do anything to address Evaporative Emissions.

The goal is to satisfy federal air quality standards. Vehicles with valve guide seal problems generally emit a large amount of smoke after idling for a few minutes and may not be observed during annual inspection. There are also those driving unregistered vehicles and falsified inspections. My neighbor felt it was easier to pay $50 for a false inspection than to replace a failed oxygen sensor.

Actually the goal is to reduce airborne pollutants that are dangerous to a resident’s health. A secondary goal IMO is to reduce air pollution beyond the local area. The air quality standards are a means to meet the more basic goals.

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Much of the air pollution in PA & NJ is actually emitted from industrial smoke stacks in Ohio.