E check failure - NOx

[mattswabb]

Took my new daily driver in for e-check. 93, FI, 5 speed.

The NOx (Nitrogen/Oxygen) reading was 1872.4 ppm and the limit is 1380 ppm.

What should I check or change to pass? It already has new plugs, wires cap and rotor. Air filter was pretty dirty so after the failure I got a new one.

[packrat427]

Matt ,it could be a plugged EGR valve ,or restricted,or partially plugged in the manifold ,I would think that if the EGR valve was bad totally it would not run right ,And how is the converter ?
Sea foam it , Seafoam it , Seafoam it :lol: :lol: :lol:

[freshtiva]

Ive never had to do a "e check" is that an actual formula:

NO x ( nitrogen/Oxygen ) ? NO times ( nitrogen divided by oxygen ) ?

Do they do the test at idle ?
And what is NO?

[mattswabb]

It's tested at 25 mph under a load on a dyno.

I installed a new EGR valve tonight. I'll get some seafoam tomorrow. Should I suck it in thru a vacuum line? or put it in the tank?

EDIT Not egr but PCV

[mechanicaldj]

catalytic converter!!!!!!!!!!!!!!!!!!!!!!!

but then, who needs the worthless exhaust restricting gadget????????? :roll:

[packrat427]

It's tested at 25 mph under a load on a dyno.

I installed a new EGR valve tonight. I'll get some seafoam tomorrow. Should I suck it in thru a vacuum line? or put it in the tank?

Load it up thru the vaccum hose,like 3/4 of a can then shut it off for 30 min . then take it out and drive it like you just stole it.
And put a can in the tank also

[mattswabb]

Here are all the #'s from my test:

HC 140.6 ppm 184.0 ppm limit
CO 0.37% 1.04% limit
NO 1872.4 ppm 1380 ppm limit
CO2 14.16%

I do have a converter from a festiva that passed with 237ppm for the NO reading. I'll try the seafoam 1st. Also new egr valve, air filter and o2 sensor has now been installed


EDIT Not egr but PCV

[mechanicaldj]

now i am puzzled,

you have a EGR on your Festiva???????

my manuals say that only the Assfire had an EGR

[mattswabb]

now i am puzzled,

you have a EGR on your Festiva???????

my manuals say that only the Assfire had an EGR

egr valve

[mechanicaldj]

now i am puzzled,

you have a EGR on your Festiva???????

my manuals say that only the Assfire had an EGR

egr valve

ok yes you have a EGR VALVE!!!!
but i does not belong on a Festiva, only on the Aspire!

[mattswabb]

Sorry, meant PCV valve, my bad.

[mechanicaldj]

:roll: :roll: :roll: :roll: :roll: :roll: :roll: :roll: :roll: :roll: :roll:


just swap the catalytic converters

high NOx readings also could be caused by a lean fuel running condition
but then you would notice the knocking and pinging

[WmWatt]

I had the same same thing. It's almost certainly the EGR valve. It costs nothing to remove and clean. Very simple procedure. You can test it by gently pushing up on the diaphragm from underneath with the tip of a finger. It should move smoothly and easily. Look at www.ncf.ca/~ag384. Cars.htm for a description of cleaning an EGR valve on a carburetted '89.

It' s hardly likely the catalytic converter. Early converters (actually an afterburner) only treated carbon. Later they invented the two part converter, one part to burn leftover carbon, the new part to burn the nitrogen. I don't know when the Festiva got a two part converter, if it ever did. It has long been a scam a muffler shops to tell people they need a converter when they don't. I have a lifetime muffler guarantee on my '89 with Midas. Every time I've taken it in for a new muffler they tried to sell me a converter, even before Ontario had emissions testing. I always said no. They gave people this story that the converter was breaking up inside and shooting bits of metal back into the muffler and destroying it. When Ontario brought in emission testing I got a really low carbon reading so there was never anything wrong with my converter. Still okay after 17 years. Beware muffler shop scams.

[25Horseplay]

I had that problem too Matt. I ended up putting on a catalytic converter and resetting timing. There is no EGR valve on the FI festiva's.

[WmWatt]

That should have been www.ncf.ca/~ag384/Cars.htm. Sorry about the typo. I suspect I'm situtationally dyslexic, the situation being at a keyboard.