ISFFUN

iTrader: (4)

I did my smog today and came up with

MAX AVE MEAS
15MPH 49 / 9 / 49
25mph 33 / 6 / 33

So I'm at the limit, probably won't pass in 2 years. The numbers went up from my 2010 smog test (27 / 24). Yes, I've googled..just wondering if anyone had this case before and solved it.

Here's what doesn't make sense

Fuel filter replaced
All O2 sensors replaced
PCV replaced
Head gasket replaced
Coolant temp sensor replaced
Oil changed
Air filter changed

I keep reading around about how it could be bad intake/exhaust valves (stupidly did not replace/test these when the head gasket was done) or air intake leaks...I have no idea what to look at next. The cats would be my first choice, then exhaust leaks, but the car isn't running at 14.7 AFR at idle - my A/F meter is installed before the cat.

My A/F meter shows 15.5 at idle and there's that notorious strong fuel smell when the car starts for several minutes, so it's not burning fuel completely even at idle.

Could it be that ECU thing where the injector stays on? I took an automotive stethoscope and listened to each injector, they're all clicking.

Rest of the numbers -
%CO2 / %O2 / HC PPM / CO % / NO PPM
15mph
14.2 / 0.4 / 49 / 0.03 / 216

scoobySC3

iTrader: (1)

The start up fuel smell is normal for any car as the cats demand a bunch of heat before they will start working. If you are looking for a cheap and dirty way to pass, throw some E-85 in the tank or pure alcohol like everclear. Then right before you get the test, go beat the ever living **** out of the car to get those cats as hot as they can get.

And to test the valves you could do a cylinder leak down test, or even just a simple compression check might be enough to pinpoint the problem. Also how old are the cats? They all get less effective with age, so getting some good used or new ones may not be a bad idea.

Hope this helps.
Thanks,
Rick

Ali SC3

iTrader: (10)

15.5 is Lean, not rich so your car is running more or less normal. it should be a perfect 14.8 but the GE ecu will idle a little lean from time to time.
It really doesn't make any sense to have a strong fuel smell and having a 15.5 AFR unless you have an exhaust leak, the engine is misfiring (shows up as false lean), or there isn't really a strong fuel smell/ the wideband isnt working right. I think the wideband is fine cause thats a normal idle AFR for the GE ecu.

My engine runs very healthy even as na-t, as I had even refreshed everything, then a year ago I had the same issue my numbers were just higher than the previous years and I barely didn't pass. It was the cat, the original finally let go. changed the cat and all the numbers came down a little bit except for nox which i think was well within the limit anyways.

ISFFUN

iTrader: (4)

OK, I'll just go with the exhaust leak / cat idea. Car is 1997 from the Ohio area, plenty of rust on the exhaust and steel parts.

Replace the whole exhaust system..ugh $$$

Thanks for the input.

UZinator

iTrader: (1)

Sounds like like bad cat to me.

topdog849

iTrader: (1)

adding some acetone to your gas will help HC numbers. aswell as a good seafoam treatment and new plugs in that order.