Passed Aircare with high NOX - what to test first

My Dodge Caravan 3.3l (270,000 klics) has passed aircare but with nox
reading that are 50% above average. I'd like to adjust one thing at a
time an retest. What is the most likely cause.

- dirty air filter (never replaced)
- spark plugs (never replaced)
- EGR valve (is this ever the problem)
- O2 sensor etc.

Thanks

Year

On Sep 27, 8:15*pm, xxx > wrote:
> My Dodge Caravan 3.3l (270,000 klics) has passed aircare but with nox
> reading that are 50% above average. I'd like to adjust one thing at a
> time an retest. What is the most likely cause.
>
> - dirty air filter (never replaced)
> - spark plugs (never replaced)
> - EGR valve (is this ever the problem)
> - O2 sensor etc.
>
> Thanks
>
> Year

That should be;

Year NOx Average
2007 895 732
2008 953 671
2009 976 656

xxx > wrote in
:

> My Dodge Caravan 3.3l (270,000 klics) has passed aircare but with nox
> reading that are 50% above average. I'd like to adjust one thing at a
> time an retest. What is the most likely cause.
>
> - dirty air filter (never replaced)
> - spark plugs (never replaced)
> - EGR valve (is this ever the problem)
> - O2 sensor etc.
>
You've *never* replaced your spark plugs *or* your air filter? If you're
the original owner or didn't buy it less than 100,00 Km ago I'd change
those first. Look at the owners manual on a *regular* basis. These things
(among others you've probably missed too) *need* to be replaced.

In article >,
xxx > wrote:
>My Dodge Caravan 3.3l (270,000 klics) has passed aircare but with nox
>reading that are 50% above average. I'd like to adjust one thing at a
>time an retest. What is the most likely cause.
>
>- dirty air filter (never replaced)
>- spark plugs (never replaced)
>- EGR valve (is this ever the problem)
>- O2 sensor etc.

Wait a minute... you are at 162,000 miles with the original air filter and
original plugs?

Do you do ANY maintenance at all on this car?
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

"Scott Dorsey" > wrote in message news:h9qjl6$t9
> Do you do ANY maintenance at all on this car?
> --scott

That downright turns my stomach... You reckon he ever changed oil
or serviced the tranny?

On Sep 28, 12:18*pm, "hls" > wrote:
> "Scott Dorsey" > wrote in message news:h9qjl6$t9
> > Do you do ANY maintenance at all on this car?
> > --scott
>
> That downright turns my stomach... You reckon he ever changed oil
> or serviced the tranny?

Folks who live in Lotus Land are in a different world.

On Sun, 27 Sep 2009 20:15:28 -0700, xxx wrote:

> My Dodge Caravan 3.3l (270,000 klics) has passed aircare but with nox
> reading that are 50% above average. I'd like to adjust one thing at a time
> an retest. What is the most likely cause.
>
> - dirty air filter (never replaced)
> - spark plugs (never replaced)
> - EGR valve (is this ever the problem) - O2 sensor etc.
>
> Thanks
>
> Year

Chances are the spark plugs with new wires and a new air filter will
correct this issue.

>
> > - dirty air filter (never replaced in the 5 years, 50,000 km that I've owned it)
> > - spark plugs (never replaced in the 5 years, 50,000 km that I've owned it)
> > - EGR valve (is this ever the problem)
> > - O2 sensor etc.
>
> You've *never* replaced your spark plugs *or* your air filter? If you're
> the original owner or didn't buy it less than 100,00 Km ago I'd change
> those first. Look at the owners manual on a *regular* basis. These things
> (among others you've probably missed too) *need* to be replaced.