Quote
What should approximate inlet and outlet side temperatures be anyway? Also, since EGR controls combustion temperatures, and I still have the persistent cold start-no idle situation, could whatever that is be affecting my NOX reading?


Not sure what the temps should be but if the cat is functioning properly then the outlet temp should be higher than the inlet temp. If you end up needing a new converter try Greg at Mighty Muffler on Cave Creek Rd North of Dunlap.

Your cold start issue could be related but I doubt it. If the EGR valve were stuck open then it would idle rough and could stall on cold starts, but it would not be affecting your NOx when warmed up and doing anything other than idling (like while emission testing). If the EGR valve is not opening at all then it would contribute to high NOx readings but wouldn't have any affect on your idle or cold starting.

95 Montero SR
3.8 MIVEC, Advance headers, 2 1/2" exhaust, Magnaflow muffler, OME shocks & rear springs, 2" body lift, 3" tank lift, 4.90s, TRE front locker, factory rear locker, Roger Brown Rock Sliderz, 315/75r16 (35") tires, Sport big brakes