LT1 PWRD

For the past 12 years, the camaro never had a problem passing and now that
I'm selling the car, it has to go wrong! It's mandatory in Ontario to pass emissions test to plate the car.

Here are the values the test revealed:

Testing at 40 kms/hr:

_________allowed_________Reading
HC PPM: ____55___________ 136__________Fail
CO % : ____0.31__________0.05__________Pass
NO PPM:____0408__________146___________Pass

Testing at Idle:

-----------allowed----------Reading
HC PPM:-----200-------------126------------Pass
CO % :-------1--------------0.03------------Pass


So the only thing that fails the car is the Hydrocarbon reading at 40 km/hr
by almost 3 times the allowable limit. The car runs awesome, the O2 sensors
aren't very old and look great (physically), however the cat is still original
and I don't drive the car as much as I used to..

Any ideas? Any help would be GREATLY appreciated.

Thanks,
Martin

Z28LT1_Just_Nasty

12 year old cat, might as well replace it.

LT1 PWRD

If i was keeping the car, I wouldn't mind changing a bunch of parts but since I'm selling it, I really hope it ain't the cat. That would be quite pricey.

neil350

You can get an after market unit fairly cheap

LT1 PWRD

Well, I changed the plugs, put the factory air box with new filter on and went for a 100 mile trip and got it retested and it still Failed BUT my HC readings were a much better 67 instead of 136!!!

The dealer will scan it, hopefully they'll find something.........I'm really paranoid that they'll say they can't find out the cause for some reason.

I guess I'll have to start buying some new parts and do a process of elimination.

Last year, this car had readings of 1 ppm. What gives!?

Z28LT1_Just_Nasty

Cats work better once warmed up, still think its the cat.

LT1 PWRD

I'm starting to think that way too. What can I expect to pay for an oem cat?

Z28LT1_Just_Nasty

Well if you don't car about performance and just passing emissions the cheapo universal cats are like 50 bucks off summit

http://store.summitracing.com/partde...5&autoview=sku

LT1 PWRD

Hey, that's cheap, thanks. So with the slip fit like that you just basically use clamps? The other cats I've seen come welded to a whole new Y-pipe, that's why they're so much more money.

My MAF was a tad dirty too and I'm getting the injectors flushed. It's needed for sure.

Injuneer

High HC, combined with low CO is generally a sign of a leaking injector.

LT1 PWRD

Thanks Fred, good to know. The car didn't throw a code, maybe I'll ask them
to check em.

sn8ke eatr

go on a long trip with the car, get the motor really hot- itl burn cleaner that way.

also u might as well try one of those bottles of stuff that gaurentee your car to pass inspection. its cheap enough and beleive it or not it worked on an old ford probe i had.

good luck

My94T/A

Well in my 94 bird i had a similar problem, after i bought it...i had the opti, plugs, wires, waterpump, elbow, maf sensor changed. So after that the car ran like a champ..but when i went for the emissions test I failed, one of the numbers were really high don't remember which one.....this was 3 years ago. But long story short took it to the GM dealer, they took a look at it and found one of my injectors to be blocked and one to be leaking. Had those changed and passed the emission with flying colors. So if you want you can take a look at the injectors like Injuneer said. They might be the cause. Good luck

Severous01

i'd also say you're rich. doesnt matter how much gas the cat is changing ... if there's too much fuel in the exhaust then ther'll be high HC's.

i'd say to run some GM fuel system cleaner....the good stuff you put in the rail, not in the tank....and run that for 20 or 30 minutes. then see where you;'re at. if you have access to a scan tool you can read your ox levels at live time. they can tell you if you're rich still or not.

Injuneer

A leaking injector will not affect the O2 sensor readings..... an O2 sensor can only "see" (surprise ) oxygen.