bored smog tech here

[sc ka24e]

my s14 barley fails at 15mph but passes nice on 25.. its nox are high.. ive repaced all kinds of stuff (new cat) egr lines etc..... can u tell me a secret to pass... i know u guys dissconnect things to help it out lol....

OOps n/M just saw vvti s post.... lol.. ill figure it out... hope u get some work in.. its tuff all over the country.. especially CA........

[techn9ne]

Originally Posted by sc ka24e

my s14 barley fails at 15mph but passes nice on 25.. its nox are high.. ive repaced all kinds of stuff (new cat) egr lines etc..... can u tell me a secret to pass... i know u guys dissconnect things to help it out lol....

OOps n/M just saw vvti s post.... lol.. ill figure it out... hope u get some work in.. its tuff all over the country.. especially CA........

so you replaced the egr and cat and its still failing? double check the timing (too for advanced creates NOx.) NOx is also an indicator of lean fuel/air ratio and/or high cylinder temperature. so if it gets serious, check for stuck closed or clogged injectors, carbon deposits, and small gnomes that run around inside the exhaust.