[mk3glx]

So here in Ohio all cars need an emmisions check. Last week my 88 I4 failed because of very high N02 numbers. It passed fine 2 years ago.

I was told it could be the Catalytic converter? Any other ideas as to how to get down this number without spending the big bucks?

Thanks!

 

[emerald_gen3]

u might check/clean your EGR valve... its supposed to help reduce that type of emission... i used to have an old ford w/ the same problem. egr cleaning fixed it.

 

[mk3glx]

Anyone have tips for cleaning the EGR valve?

 

[Lord_Anarchy]

I know that the auto parts stores carry "emisson chems" that clean out your sys or whatever. Anyways, they say "We guarantee you will pass your next test or your money back" I've used it once in my old '86 Celica GT-S and it passed.

 

[rawdawg]

When mine didn't pass(a couple of months ago), it ended up being the O2 sensor.

 

[karazy]

Check the dist cap and rotor. Also take it for a little cruise on the highway before being tested.

There is a filter on the EGR vacuum modulator that can be removed and cleaned as well.

 

[mike787]

For your year... if I had to make an educated guess, it wud most likely be the 02 sensor.

 

[mk3glx]

From my research it appears that the O2 sensor doesn't effect the NO2 as much as the EGR & Catalytic converter do.

Shouldn't I be throwing a CEL if the O2 sensor is going out?

 

[mike787]

Do what I did....get an OBDII code reader to retrieve the error code... do some trouble shooting in the area suggested by the dianostic code to pin point the exact component ...test it and if defective, replace that part and viola!!! my car passes Air Care. Note: I did have to replace a ERG Valve Sensor on my 97 Camry at 145k km, when it failed Emissions check or Air Care as we call it in our neck of the woods.

 

[mike787]

Opps... ..I just realize your car is an 88 and not a 98.. ..so OBDII diagost is not applicable in your case but you still can do the flashing engine light test to retrieve the emissions dianostic code and procede from there( see the Haynes Repair Manual for procedure).

 

[mk3glx]

Thanks for the replys. This weekend I took off the EGR valve and it was 90% clogged with carbon, wow! I did this so maybe it will pass this week:

-Cleaned EGR valve & throttle body
-Changed spark plugs, cap & wires
-oil change
-ATF filter & fluid change
-New O2 sensor

It seems to run better and the exhaust smells less "gassy", hopefully it will pass.

 

[90celica]

good luck!!!

 

[emerald_gen3]

that should take care of it man... let us know how ur next test goes