Topic: High Nox readings.....Failed Smog yet again. Help!

[87toyotaman]

First off its an 87 22r. The past 3 years I passed with flying colors now all of a sudden I'm getting high NOX readings.

What I've done....

Cleaned air filer

New Cat

New Spark Plugs/wires

New Gas cap

Idles perfect

Drove and hour before test

Running 87 octane with guaranteed to pass


What it could be.....

[Snowtoy]

With a new CA cat on it already, you might try pulling and cleaning the EGR valve and checking the air injection valve(if it is a CA smog equipped vehicle).  On an '86 I restored about 5yrs ago the Air injection valve was bad causing high NOX, fortunately I had a spare, new ones run about $300.

[Slolyfe]

With a new CA cat on it already, you might try pulling and cleaning the EGR valve and checking the air injection valve(if it is a CA smog equipped vehicle).  On an '86 I restored about 5yrs ago the Air injection valve was bad causing high NOX, fortunately I had a spare, new ones run about $300.

I have those parts. my truck passed 1 year ago. pm me

[kneedownnate]

I've always gently scraped them out with whatever fit, but I don't see compressed air being any good for it.

[TRACKER]

With a new CA cat on it already, you might try pulling and cleaning the EGR valve and checking the air injection valve(if it is a CA smog equipped vehicle).  On an '86 I restored about 5yrs ago the Air injection valve was bad causing high NOX, fortunately I had a spare, new ones run about $300.

check egr and port

[87toyotaman [OP]]

check egr and port

That was it  Thanks