Originally Posted by Ryan Laliberte
NOx is measured at Cruise, this is only when your EGR opens.

Originally Posted by Tim Grech - Emissions 101

EGR SYSTEM
The EGR is another system which many people eliminate. Now, other then dirtying up the intake manifold with a little extra carbon, the EGR does not affect the performance of the car in any way. It’s closed at WOT and idle. It’s only open at partial throttle w/ no boost to be precise. If you are doing your emissions and you are failing miserably in the NOx department (FWD only), your EGR is not functioning correctly. To understand this, you have to understand that NOx is not created by the burn of the motor but by the heat of the motor. At around 2500 degrees F, nitrogen and oxygen in the air effectively combine to create NOx, a harmful gas. The EGR re-circulates inert exhaust gases back into the intake to cool down the hot burn and reduce the NOx being formed.


If you have link, you can richen up your fuel sliders at the RPM where they test at (About 2500ish) to dump a little more fuel so it cools your burn.


If you have DSMLink, no you can't do this. Fuel sliders are for open loop tuning only & the car won't be in open loop when doing an etest (or at cruise). It will be in closed loop, which gets feedbacks from the O2 sensor, so even if you were to richen things up, the ecu would just try & compensate to get your trims back inline. Only way to richen it up would be to add so much fuel that the ecu can no longer compensate but that will cause other issues (throw a CEL, probably not pass other portions of the test).

The way to do it with link would be to reduce your timing sliders at the specific test rpms. As the timing sliders are always in effect.

98 Eclipse GSX DSM82HTA