New to Toyota Nation

[Talitha]

Hi there, Im a first time toyota owner. I own a '84 corolla which I inherited from my mum. It runs pretty well. I need it to pass air care so i can use it in the lower mainland. I took it in once and it passed on most things in the test except the Oxides of Nitrogen emissions in the driving portion. Im wondering if it has something to do with my exhaust system or if there are any suggestions out there?

Thanks!!!

[Criard]

sound like it could be exhaust.

unfortunately this forum is almost dead compared to how often people used to post on here.

[Talitha]

Thanks!

my dad said it could also be the catalytic converter.
I was just wondering if you know if there are any other sensor systems on the car.

[TheGreenMachine]

new to toyota nation myself, but i am a smog tech student. if your car passed on everything except NOx, it could be your Exhaust Gas Relay (EGR). basic review: when your combustion chamber goes over 2500 F, NOx forms, has a photochemical reaction with sunlight, and turns into smog. Your EGR eliminates this by recirculating inert exhaust gasses into your chamber. this reduces temperature and lowers NOx emmisions.

Sorry if you live outside the US, not sure if the rest of the world uses this, but that would be the thing to check IMO

[verlaryder]

The EGR valve may not be working causing high NOx readings. Sometimes the EGR pipes get clogged with carbon too.

Unlikely to be a worn out catalytic converter because then your HC and CO readings would be high too.

Try replacing all the spark plugs before the test and also drive on the freeway for 5-10 miles prior to taking the test. You want the motor to be fully warmed up when the test is conducted to help generate low emission readings.

[Talitha]

thank you for your help! i really appreciate it!

I've been looking into this but now im having other problems.

the car ran out of gas last month and it hasnt really been the same since. I dont know if that is the reason why or if it just triggered something else because the car would start stalling when i would drive it, take two or three tries to get started and now it wont start at all! It has never had any problems like this before so I am not sure where to begin. Any suggestions would be greatly appreciated so that i can start narrowing down the problem!

Cheers,

Talitha

[Talitha]

I was reading up online and im also wondering if it has to do with the fuel filter and/or cleaning the spark plugs....