rockygs300

I could use some advice if anyone is wise in the emissions testing arena. Any suggestions would be greatly appreciated.

This first time I failed I used the Guaranteed to Pass additive. It lowered the NOx a bit but still failed.
The last time I replaced the air filter and cleaned the MAF with the appropriate cleaner - I forget the name. It has been a great car but I am only planning to keep it through the winter and don't want to sink a lot of money in it. Does anyone have any suggestions based on the readings?

24-Sep-2012 * *
HC 0.5263 * * * * * *
CO 9.0012 * * * * * *
CO2 361.2395 * *
NOx * * *1.6356 * * * * * *
--------------------
28-Sep-2012 * * * *
HC * * *0.4177
CO * * *6.8524 **
CO2 * * 346.8265
NOX * * 1.5174
--------------------
13-Oct-2012 * * * **
HC * * 0.4105
CO * * 7.0311
CO2 * *370.6623
NOX * *1.5867*
--------------------
LIMITS(passing)
HC * * 1.2
CO * * 15
CO2
NOX * *1.5


If the formatting is off let me know and I will try a different format. Thanks.

GS4_Fiend

iTrader: (22)

HC and Nox should be measured in PPM. And CO,CO2, O2 should be measured in %. Relist them in that format

jcat_350

what grade of gas are you using? Where are you buying it from? Does it contain any ethanol?

The first thing I can think of is to run fuel system cleaner through the car...I've never heard of this 'guaranteed to pass' additive, nor should the car need it. The car IS 14 years old though, so the cats might have had it.

raytseng

hrm,
it seems you're pretty close to passing..."maybe" some quick bandaids will get you over the hump (but yes you have a bigger problem).

change/check PCV valve ($5)

Try a fuel injector cleaner to see if that will help (gumout, redline, amsoil). You can put it in extra concentrated with just a few gallons of fuel to see if that will really get things going.

Go for long hard drives through that tank to see if that can burn out any buildup.

Fill up with premium prior to test.
day of the test; go in with engine hot (but not driven hard).

If this doesn't work, I suggest you'll have to bite the bullet and take into shop to find out what really is wrong and how much you really need to fix it. (probably a bigger bill).

If you plan to junk the car, you could just drive it illegally for the next few months...but that's a risk you need to consider if you get caught. Also, you won't be able to sell your car very well without smog check I think (will be able to junk it as a donation)

rockygs300

Thanks for the feedback. I will try the injector cleaner and change the PCV valve. The car was driven hard (30 min at ~70 mph) prior to the last 2 tests.

I'm afraid to see what a new cat will cost. If anyone knows of an economical brand that does the job I would be grateful to hear about it.

Thanks again