Crazy nox reading on 93 KA

[kingkilburn]

I just took my car to get smogged and my nox reading at 15mph was 3000+ with a slightly elevated hc reading. At 25mph the hc reading is well within tolerance but the nox is still too high.

I have replaced the cat and O2 sensor. All the vacuum lines are new. No cel. The passage way from the egr has been cleaned(pain in the ass).

What do you guys think?

[blktopsr20]

seafoam it

[kingkilburn]

I have seafoamed it twice.

[ka4life87]

Nox is mainly egr valve related, check and make sure egr is not clogged also check solenoid which activates egr could be bad

[kingkilburn]

The egr is working but I'm not sure about the system that triggers it.

[wangan_cruiser]

theres already an open thread about this issue. search it. i think the op is name singlecamslam.