Hey guys,

So...I did my e-test...and the car bombed it.

Here are the results:

Curb Idle:

HC ppm - limit: 200, reading: 144 (PASS)
CO % - limit 1, reading 0.56 (PASS)

40km/h:

HC ppm - limit 55, reading 94 (FAIL)
CO % - limit 0.31, reading 2.68 (definitely FAIL)
NO ppm - limit 612, reading 785 (FAIL)


So...I guess I'm kinda SOL...it didn't just fail, it completely BOMBED the 40km/h test. I don't think that would even pass if it was tested as a hotrod.


I just checked under the car - the piping going back from the cat looks like it was replaced recently, but the cat forward (including the cat) looks like it has been on the car much longer. It still looks solid, but I'm guessing its pretty old.

Besides the cat, any suggestions? I posted everything done to the car recently in this thread:

https://www.thirdgen.org/forums/thir...ng-e-test.html

Any suggestions appreciated.

Thanks,

--Mike

 

what type of plugs did you put it the car? did you make sure it was warmed up really good before you went for the test? Check and make sure the fire order is correct(i have seen a car fail for this before).

Also has anybody ever put a bigger cam in this car, or are the injectors the stock size for it. there are so many variables that it could be anything.

 

I just sent an email to the previous owner asking about the plugs.

the injectors are 19 lb accels, so they should be the same as stock.

the car was definitely warm going into the test.

My tentative plan of action is to replace the t-stat with a 195 degree, get a new cat, and change the air filter. I also asked the previous owner when the last time he did an oil change was, and depending on when that was, I'll do an oil and filter change.

Considering the fuel filter, coil, cap/rotor, o2 sensor and EGR were done within the last 3 years / 10,000km, I don't think there is much point in messing around with those, but correct me if I'm wrong.

And the motor is completely stock.

--Mike

 

Is your car have a single cat or a dual cat setup? I've got a factory dual cat y-pipe off my GTA here with brand newish cats on them if you want. Just pick them up and they are yours.

Another thing you may want to do is drain your tank down to about 1/8th of a tank and dump a gallon of methel hydrate (you can get it at TSC) in your tank. It will reduce your HC and CO%. It works for most people. If you do a quick search here you'll find it gets used a fair bit by folks. I suspect though that you are on the right track by replacing the t-stat and cat though.

 

The high CO indicates a improper air fuel ratio ( usualy too rich). The high NOX indicates a lean afr and or a inoperative EGR.
Could be a vacuum leak on one cylinder. Causing the computer to compensate with more fuel makeing the other 7 cylinders over rich. or a faulty injector. May not be running in closed loop mode. The cat is probabily working.

 

I have a single cat setup on my car. What would be involved in going from the single cat to the dual cat setup? I figure it might be cheaper then paying for a new cat and getting it installed. If it isn't too involved, I'd love to take those cats off your hands

What if I just chopped off one of the cats and replaced mine with it? Would that work perhaps?

The exhaust does smell like it is running a bit rich, but I'm not sure what could be causing it. Wouldn't a vacuum leak be pretty obvious? The car does appear to run quite well.

Perhaps I'll just dish out the $100 for a diagnostics test...or try doing the cheap fixes first, and if that doesn't work out, take the diagnostics test.

--Mike

 

Dang that sucks. My 90 GMC Sierra with 477k KMs on it just passe with flying colors! Original engine too!! God bless the general!!!

 

Get rid of that 175 degree thermostat its to cold for your engine with running a stock chip. Its not letting your car get into closed loop and I too was burning super rich at one time. I put a 195 degree in and everything leaned out and ran alot better. If your cats are old they could be a problem aswell but I doubt it. Try the thermostat first.

 

Mike, you would have to remove your stock y-pipe from the manifolds then cut it just past the cat. The dual cat one should fit in place, but you would have to get someone to weld up the exit to the old cat back, and probably need a new hanger to support the y-pipe. I don't think you could replace the existing cat with one of the ones on the dual setup. The dual cats are smaller.