89 240sx emissions help

[crzycrkr]

I have a stock 89 240sx and am having trouble getting it to pass smog. The nox is way to high. I have replaced the EGR and BPT valves, but still no good. According to the test station the egr is not opening as the rpm's go up. Is the EGR control seliniod valve what I need to replace? Or something different? Real low on money right now too, so taking it to a mechanic isn't really an option. Quick help would be greatly appreciated and thanks in advance.

[crzycrkr]

Actually, the egr does seem to be opening as the rpm's go up, but I do not know if it is opening as much as it should. Anyone know how to check this? Thanks

[180fan]

The vacuum hoses at the bottom of the BPT to the EGR is a common place for failure. Replace the hose that can fatigue from heat and age and will collapse under vacuum or gets a hole in it frequently.