Arizona Emissions Standards for MG's

by Les Bengtson

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Recently, as I waited in line trying to get the 68GT through emissions testing (re-check after failing the first check for high CO—less than 0.5%) I was thinking of the old Office of Strategic Services—the OSS.  They were formed just before World War II to provide an intelligence gathering and sabotage capability. One of the special weapons that was developed for their use was a very small, single shot weapon to be used if the agent was captured and might later have to kill a guard to escape.   Since this was a single shot weapon, and could not be reloaded, you had to pick the time to use it very carefully or you would either be re-captured or killed. There is one successful use of this weapon recorded. The reason I was thinking about this, is that I was considering using my own single shot weapon at this time if my car did not pass the emissions testing—the emissions waiver.

The emissions waiver is a once in the lifetime of the car waiver of emissions testing, designed to allow you one year to get the car into compliance.  To get the waiver, you have to fail the initial emissions inspection, spend a certain number of dollars on repairs (amount depends on model year), fail the initial re-check, then go for another test at the special waiver station, bringing along supporting documents to show that the required amount of money has been spent on repairs. The waiver station can then grant you a one year waiver, allowing you to register your car for one more year.  If it will not pass the emissions test the next year, you have to fix the car so it will, quit driving the car, or sell it.  The fact that a waiver has been previously issued is recorded by the Motor Vehicle Division and will show up when a title or registration transfer takes place. Anyone who is buying a car needs to ask if there is a waiver on record. Since it is one per life time of the car, not once per owner, if the car has been previously waivered, it can never be waivered again. This means that, if you buy a car that has been waivered in the past and it fails the emissions testing, it will have to be fixed or sidelined. The state will not give you any grace period to bring the car into compliance. To me, the fact that a car has been waivered in the past would significantly lower the price I would pay for it.

In any event, my car passed on the re-check, relieving me of having to make the decision on using my waiver right.  I was able to order new needles from Joe Curto in New York and get the car through. The fact it ran poorly was not a factor in meeting the emissions test. The only needles available were a set that was too lean for proper running. The slightly richer needles—the ones which will both allow the car to run properly and meet the emissions standards had to be ordered from Burlen Fuel Systems in England. It took over two and one half weeks from the time of my telephone call until the needles arrived—shipped by air.  You can take your car in for inspection the month before the registration renewal month and the inspection will count towards your renewal. This might be a very good habit to get into.

 While I was at the inspection station, and in a good mood from having passed, I spoke with the office people about exactly what the standards are. They were able to help me find out whom in the system to contact and the current emissions standards for our MG's were made available.  I have prepared a table that will show you what standards you have to meet to pass. Unfortunately, they will only help with the idle settings. The “cruise” standards require the use of a dynamometer to take the readings while the engine is running under load—that is what those rollers are at the emissions testing sites. You can get the use of a dynamometer locally, but it costs $100 per hour. To me, this is only worth it if the engine is really marginal and might not pass otherwise.



Idle Standard Cruise Standard


500 ppm 500 ppm
CO 5.5% 4.2%


HC 400 ppm 400 ppm
CO 5.5% 4.2%


HC 250 ppm 250 ppm
CO 2.2% 2.2%


HC 220 ppm 220 ppm
CO 2.2% 1.65%


HC 220 ppm 220 ppm
CO 1.2% 1.2%

It should be noted that emissions standards vary by weight class and these apply only to the MG's. As with everything else, they are subject to change without notice.


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