Re: Emission Testing: NOx

["Harold McElraft" <hmcelraft@xxxx>]

1500 sounds about right for emmissions test limit on an 81 but the D 
should pass at less than 1000. You are probably as you suspect 
running too lean. This could occur with some failed fuel mechanicals 
or a combination like a bad oxygen sensor and vacuum leaks. You 
didn't say what the CO, HC and CO2 readings were. These readings can 
provide some clues also. Are you sure the frequency valve is working 
by checking the wires and being sure it is buzzing?

Harold McElraft - 3354


--- In dmcnews@xxxxxxxxxxxxxxx, "George Ryerson" <TRyerson@xxxx> 
wrote:
> Hi All,
> 
> I have a yellow painted '83 in Akron Ohio and ran into some 
problems last
> Friday when trying to get through the emissions testing in Akron. 
In
> previous tests since 1997, when I bought the car, it passed with 
flying
> colors. This time though apparently the Ohio tests now include NO 
( nitrogen
> oxides ) testing which my car failed with a reading of 1650 
against a max
> allowable of 1500 ( I believe ).
> 
> If anyone out there has any suggestions, I'd really appreciate 
hearing them
> as all I can think to do is to richen up the mixture a little as 
NOx is
> produced by higher combustion temps. Perhaps also retard the spark 
a little.
> I don't hold out much hope for these two dodges since they would 
both tend
> to raise the hydrocarbons.
> 
> As always thanks in advance to the list.
> 
> George Ryerson