PASSED ! I didn't make any changes, like plugs or different gas, I
wanted to see what would happen if I just did what most of you do,
that is get it hot (steady state cruise/drive at 2K rpm 40 min) then pull
right onto the rollers -- Bingo, pass
Thanks to all who assisted & Mark I'll use your guy next time

 

Woah, thats a huge difference.

 

You went WAY up on NOX. Any more and you wouldn't have passed on THAT side of the sheet.

 

NOX is very high, where was the temp gauge when they tested it?

 

You have a lean misfire. Might be an air leak, but most likely a partially-plugged injector (or more...) Get the injectors cleaned or replace them, and things will go better for the engine. The smog readings are telling you something.

 

The ethanol/hot drive should work. I always did that when I lived in Connecticut; never failed. Another possibility is move to Wyoming; don't need a cat because there is no test.

 

Well, congrats on passing, but there is still something wrong. In all my earlier tests until my recent failure, O2 was less than 0.3%. I'm not sure what can account for excess O2 other than an intake or exhaust leak or a miss fire. You did a remarkable job dropping the HC. But then NO went kablooey and you barely passed. Now, as Bob says, it looks more like an air leak and lean condition, where before it looked like an ignition miss. Maybe someone can piece this together. Something seems to be wrong, but I understand that if the car appears to be performing nicely and you pass smog, that's enough to make most people real happy.

 

My GTS failed miserably this week as well. It usually runs so clean that they think their machine is broken..
Took it to Seans to see what was up, he found a huge crack in the hose to the ISV under the intake.

Time for my intake resfresh...

 

Chuck: For our edification, do you have the gas read outs from the failed test to share with us?

 

B.C. Yep ..
Imo00 it was at the 3/4 mark/line maybe a little past
Dr Bob They are new injectors and everything went well
when it was Sharktuned by Rob E.
Bill I think I hear an air leak (exh leak) where
the X-pipe is connected to the cat, Can this cause the
NO to go kablooey ?

 

Bill,
I'll scan in and upload tomorrow night after work.

 

No, the air leak would be at the intake to get the mixture in the combustion chamber lean. I'd be looking for an individual cylinder problem. First step for me would be a full-load run with immediate engine shut-off, and check the plug color.

 

I got historic plate for the 911 and 928. No more inspection for those cars in my fleet.

 

Good if that's an option. Here in the great and socialist republik of Kalleefawnya, no 928 does or will ever qualify under the current formula.

----

Smog checks are an inconvenience especially if you fail, but perhaps more importantly they help bring attention to problems the car might be experiencing. My car was experiencing a slow decline in performance as the injectors aged. Telltale was the slowly increasing NOx readings. Car seemed to run fine prior to injector replacement, but definitely improved noticeably after. The car was trying to tell me it wasn't quite perfect, via the tailpipe test. Don't ignore the messages your car is sharing with you.

 

Bill,
Here is my Fail info.
Large Crack in hose to ISV seems to be Air Leak Culprit..