Hello,
My 89 2.8 Firebird failed Colorado Emissions today, they gave me a graph for a "Technician" to interpret. I was hoping that some one here would know what it meant and what might be causing the high HC and CO. Here are the Scans...I'll put the readings here and the graph one the next post.

 

This is the Graph:

 

well i'm not positive on this but the only thing that does stuff with the exhaust are the 02 sensors that i'm aware of. other then that guess i have no idea.

 

I replace to O2 sensor right before the Emission Test.

 

how about the egr?

 

The EGR is not stuck. how can I check that it opens at the right time? I think I read that it opens when it hit 35 MPH, how am I supposed to check that?

I found a vacuum line that was disconnected. Its the line that Ts off from the Vac line that goes to the Cruise Solenoid and goes down to under the Batt. any ideas what that is supposed to be hooked up to?

Low Vacuum cases high HC doesn't it? If so why is that?

 

the compy richens the mix to try to keep the engine running IIRC.


Yep, the vacuum line off will cause probs, but looks like you might need to look into a full tuneup, and maybe a new cat.

 

Im sorry but what does IIRC mean?

 

THe NOx would be higher if the EGR wasn't working.

 

If I Remember Correctly

 

would Fuel Injector cleaner cause it to fail?

 

not normally...

 

I was going to take the Cat off to see it was just an empty shell and its welded on.
so what I'm going to do is drill a small hole in the side and stick a pice of wire in there to see if its hollow. then I just put a screw in the hole. or replace the whole thing if its empty.

 

Figured I would also throw a word in or two..
you failed for high HC
and for CO which means your getting way too much fuel or not enough air... I going to guess too much gas
which from the look of the graph means he is running pig rich, but you might already have known that. trying looking thigs over with the car... are all the hoses in the right place.. esplically the one that goes to your MAP sensor.. becasue that also control how much fuel the car gets. it could be a lot of things but I'ts not releated to the egr so stop looking at that. Let me know how you make out

 

I thought it might be the MAF i'm going to check the codes to see what it says.

 

Yep the cats hallow...