Failed Ontario Emissions Test......

Well I took my '95 Blazer to get "E-tested today"...and I failed, which sucks. The truck idles rough and sometimes wants to die (has been running better lately), but I thought what the heck i'll bring it in for the test and see how she goes, well it didn't go too great. I just changed the plugs in the Truck on saturday....Here are my readings, and information that anyone would have would REALLY appreciated....Readings:

Highway RPM test
HC PPM- Limit-50, Reading- 415 FAIL
CO%- Limit-0.28, Reading- 1.29 FAIL
NO PPM- Limit 696, Reading- 19 PASS
RPM-2011 VALID
Dilution-15.4 VALID


Curb Idle Test
HC PPM- Limit- 200, Reading- 119 PASS
CO%- Limit- 1.00, Reading- 0.87
NO PPM- N/A, N/A
RPM 1131 VALID
Dilution-14.9 VALID


Idle test went great (which is surprising?)...but the higher RPM test didn't go as planned lol. I am not too sure what the two reading that I failed even mean, some information there would help. I'm really thinking it's the Cat, and i'm likely going to be buying one tomorrow....any other recomondations?? Also, how do you TEST the Oxygen Sensors?? Any help? :)

You might be right with the cat, but I'd also be looking for a vacuum leak. Your HC at idle is on the high side, passable but high.

Alright, i'll look into that. I'm gonna buy the Cat tomorrow, and put 'er on...then do another test and see how she goes.

i had the same problem with my s10 .. checked for a vacum leak and had none . so i replace my plugs and wires and re did the the timing and it came threw with flying colors. also if there is a line at the emissions station dont let your car just idle at normal rpm keep the rpm up so that co2 doesnt build up in your cat... 

quote:

ORIGINAL: ChEvYhIcKkId89

if there is a line at the emissions station dont let your car just idle at normal rpm keep the rpm up so that co2 doesnt build up in your cat... 

Good info on your first post...and welcome to the forum.
I actually drive to the testing station in second gear just to make sure that my engine and exhaust are hot when I get there.

thanks

quote:

ORIGINAL: ChEvYhIcKkId89

i had the same problem with my s10 .. checked for a vacum leak and had none . so i replace my plugs and wires and re did the the timing and it came threw with flying colors. also if there is a line at the emissions station dont let your car just idle at normal rpm keep the rpm up so that co2 doesnt build up in your cat... 

That's all you did??? The truck had been sitting for awhile, so i'm figuring it sounds like a cat problem. As for the idling problem, i'm going to be getting new wires also...maybe I should get some of those tomorrow two and slap them on while i'm at it.

I do what Chevylover does(I do it on all my cars that need emission testing) I take a little detour on the highway on my way to get tested. 

quote:

ORIGINAL: Blahman20

quote:

ORIGINAL: ChEvYhIcKkId89

i had the same problem with my s10 .. checked for a vacum leak and had none . so i replace my plugs and wires and re did the the timing and it came threw with flying colors. also if there is a line at the emissions station dont let your car just idle at normal rpm keep the rpm up so that co2 doesnt build up in your cat... 

That's all you did??? The truck had been sitting for awhile, so i'm figuring it sounds like a cat problem. As for the idling problem, i'm going to be getting new wires also...maybe I should get some of those tomorrow two and slap them on while i'm at it.

ya thats all i did but check your timing too. i mean you are all ready in there so might as well

Someone from Yahoo answers told me that it could be the Intake Gasket....which I really hope it isn't. They said to check 1-02 Sensor, 2- Map Sensor, 3- Intake Gasket.....I'm still thinking the cat more than any of those, since I have no check engine light on at all. 

Oh they also said that the Intake Gasket is a weak point on the 4.3 engines???

I'm not a mod in this section but if I was I'd let you know that you can edit your post reather than post again a couple of minutes later...just keeps the clutter down.
 
HC PPM- Limit-50, Reading- 415 FAIL
CO%- Limit-0.28, Reading- 1.29 FAIL
 
Looking at your readings....what's your idle rpm?
HC is usually caused by a missfire or plug gap or vacuum leak. If you have a vacuum leak and the O2 sensor is reading a high oxygen content, it will compensate by adding fuel and therefore you would get a rich (high C/O) reading.
If the idle doesn't smooth out with the wires, check for a vacuum leak.
I don't believe it's common to have a vacuum leak at the intake manifold. The intake leaks are usually oil or coolant leaking out. Still worth checking though.

The Idle RPM for the test was 1100 or so....I already put new plugs in it. Maybe I should go get new wires for it tomorrow and put those on. How do I check for a vacuum leak?? I really have no idea....With the high CO% reading, what does that usually mean?