RallySportin'

I just failed emissions by barely being over on the NOx. Right now i have an open element air cleaner with a not so clean air filter.Will it lower the NOx if i put the stock air cleaner back on?

Dewey316

possible just a hair, nox is usualy from eithe running too hot, or too lean, or both. what where you HC's at, and what was your engine temp durring the test?

RallySportin'

Test Results: (Required/Inspection Results)

HC
1.0/.81

CO
20.0/2.7

NOx
2.2/2.37

CO2
NA/416.1


My temp was right up top at 220, would it help if i ran 160 thermostat in there?

RallySportin'

The EGR has also been replaced recently.

Dewey316

no, an 160 would likely be too cool. i would try to get the temps down to about 200* and see what happens, do you have a fan switch hooked up? if you do, run it with the fan. that should keep it right around 200* if you have the stock 195* t-stat in.

vjo90RS8

iTrader: (1)

does a lower stat even matter, i mean once your car gets to a certain temp the stat is just going to stay open right? And if you are up around 200+ it will definately stay open.

PyRo9862

The thermostat won't do too much for cooling when the car isn't moving untill the fan kicks in which is around 220. So a lower temp stat isn't going to do jack for emmissions. Leaving the fan on the entire test will keep it right in the range of whatever thermostat you have, (195 from the factory).

johnjm22

If you don't have a switch just turn the AC on.

BTW, how can you expect to pass the visual inspection with the open element?

PyRo9862

They just don't give a damn
How did I pass saftey with a cracked windsheild and a brake light out? Alot of places don't care about the visual inspection, and just run emmissions, although they will check brakes so they can do the work if they're worn, the place probably didn't do anything about my taillight because they knew I would come over there and change it myself rather than pay them .

flowmasterchevy

you would want to cut the heat on to circulate the coolant and keep the temps down while idiling....

RallySportin'

The only visual inspection they do is under the car, which i assume is to check for a cat.

So would it be better to have the AC or heat on during the test?

johnjm22

I just meant you should turn the AC on so that the fan comes on. Set it to the lowest setting.

As for the heater, I'm not sure if that will turn on the fan or not.

PyRo9862

The heater won't. Better than turning the AC on, install a fan switch
Or if your too lazy just rig the AC wires that controll the fan to keep it on, you either need to disconnect the harness and jump the 2 wires with a paper clip or somthing (probably a piece of wire would be better, I don't know if bad things happens if it grounds out), or just pulling the harness will turn the fan on on some systems.

beedo

have you replaced the egr solinoid, nox failure is due mainly to egr system, passages may be carbon restricted in intake. i have had to remove intake and clean the passages.