Failed emissions...help!

[87'N/A]

So i failed emissions today. i have no mods except i believe the previous owner got some sort of catback exhaust put on. so just a catback i guess is the only mod. anyways here are the test results i don't know exactly what all this stuff stands for so i'm just going to put in what it says.

1- HC(PPM) cruise limit:150 cruise emissions:199 Result:FAIL Idle limit:220 Idle emissions:374 Result:FAIL

2- CO(%) Cruise limit:1 Cruise emissions:6.65 Result:FAIL Idle limit:1.2 Idle emissions:5.83 Result:FAIL

So if anyone can help me out it would be greatly appreciated.

 

[87'N/A]

someone help please!!!

 

[CRE]

Checked for error codes? http://www.cygnusx1.net/Supra/TechTips/engine_error_codes.aspx

Checked your timing?

Still have a cat?

I'm not so good at reading emissions reports, these are just the first things to check.

 

[87'N/A]

so i guess i'm just going to put in new spark plugs, a new oxygen sensor, and dump in some of that "guaranteed to pass emissions" stuff. then i'll take my free retest and see what happens. fml.

 

[CRE]

WTF? Did you do any actual diagnostic work? Throw money at it if you want though.

 

[Kristian_Wraae]

I think I heard someone put a bit of alcohol in the tank together with regular gas to pass emission.

 

[87'N/A]

WTF? Did you do any actual diagnostic work? Throw money at it if you want though.

well now that i think about it the car could probably use all of these things anyways. as well as an oil change. probably a new air filter also. i'm going to put that guaranteed to pass stuff in just cause i've heard it works and well i guess it won't hurt to try it.

 

[Ma70.Ent]

The two main things to look at are the O2 sensor and obviously the catalytic converter. After that, you could retard the timing a bit. I retarded mine below the standard rating and I passed with flying colors.

 

[AJ'S 88NA]

Also wouldn't hurt to do what CRE suggested, check for codes. Easy to do and might point to another problem that would help in passing.

 

[cuel]

I think I heard someone put a bit of alcohol in the tank together with regular gas to pass emission.

Has to be denatured(rubbing alcohol is mostly water). Would be careful doing this, as well. Too much will actually do more damage. I have used this in the past with a few cars, and it helped, but not always.

I'd drop that exhaust at the cat, and see if the cat has been gutted. Won't pass emissions at all if it has, no matter what you do.

 

[Supra_Z]

did you drive straight to the station without driving around for around a half hour to 45mins?

 

[Asterix]

Do you have a measurement for NOx? High CO and HC could mean it's running rich, but the NOx number would verify that. Also, the NOx number would indicate if the EGR was working, since EGR reduces NOx. The catalyst primarily reduces NOx emissions that EGR doesn't get, but does get some CO and HC.

There is a simple test to see if your EGR system is working. The online TSRM tells you how. Of course, it also tells you how to see if the oxygen sensor is working.

Then again, if you're pulling the intake off to change the spark plugs, you'll be able to see if the EGR tube is clogged. It'll do that after 20 years, especially if your head gasket isn't pristine.

Making sure the cat is hot before taking the test is critical.

Asterix