tritron

My sc300 had filed emission recently and I had looked it over and the rubber part of after market air intake has a big crack. So I assume because of too much air is entering engine and this is cosing NOx to be high ?

Dawa

iTrader: (5)

*equals

*failed

im not sure, but either way it cant be good and needs to be fixed. it could be giving you erroneous readings to the ecu which in turn will adjust to what it thinks its reading and that is a problem for sure

Supruxes

iTrader: (2)

if its after the maf, then its unmetered air, which can cause drivabilty issues, and can cause you to fail emissions to do being rich.

INTIMAZY

iTrader: (5)

Did you have a check engine light? That would be a reason to fail.

tritron

No engine light just high NOx i am trying to figure out if catalytic converter is bad or too much air is entering. It is unmetered and unfiltered air .

KahnBB6

iTrader: (5)

I had this happen a couple of weeks ago but it wasn't during an emissions test. My intake tube after the MAF was cracked through completely by then and must have been getting worse over time because I had idle issues and acceleration issues over 4,000rpm. The valve train, among other things, was making noise.

I replaced it with a new rubber tube from Lexus and all those issues stopped. The car ran stronger, too. I can't tell you how it affected my NOx levels but I had no check engine light either.

As a temporary fix, get some two-inch black gaffer's tape and wrap it a couple of times. The Lexus part should be identical to the same rubber tube on the Supra NA, btw.

Check your spark plugs now too. Mine wore down a bit faster @30k miles after my last change which I do think this issue contributed to. They're supposed to be changed by 60k miles.

Supra Dr

iTrader: (14)

High NOx can also be EGR or timing related.