Originally Posted by
TheOtherDave™
Since you've asked about EGR, I take it the car fails because of high NOx.
First guess is it's running lean and that the aftermarket FPR is to blame.
If you've got the stock FPR, and its working, I would switch back to it for the re-test.
Belt-and-suspenders, put the OEM intake back on as well.
It first failed HCO and NOX. We didn't know it didn't have a cat.
Put a new cat on, it passed everything but NOX.
So we got the AFPR and turned the fuel pressure up a bit, it then failed HCO and NOX again, but even worse than the original time.
Turned the fuel pressure down quite a bit, and it failed NOX.
It's getting quite frustrating.
