I recently had my car tuned by STM, after some new mods. I had been dealing with an issue since the first reflash where my car will not complete OBDII monitors for O2, 02 Heater, or Catalyst. It still says
“Not Ready”, after about 1000 miles of daily driving (every conceivable load/start condition I could throw at it). I have been battling an intermittent cold start stutter, that I cannot seem to reproduce consistently. Gas mileage is back to great again ( 24mpg mixed) but something is somewhat off. The car is throwing no codes, and is otherwise fine. My question is are there any sensors that could be causing the car to not finish these monitors? I trust the flash I got from STM has been used countless times on other Evos with no issues like this, so I am pretty much ruling the flash out of the equation. The trailing 02 has been disabled to keep the SES light off with a test pipe. If I can’t get this sorted out fairly soon I will be making the trip back out to Rochester to have them take a look at it.

 

I would think that with 1000 miles since the flash, all your monitors should have dropped by now. Is there a reason you are trying to set all the monitors, state emissions?

I would give STM a call and get their opinion first.

 

Yeah without having the car infront of them STM really can't help much, I've spoke with Emery and they don't really have an idea what it could be. I'm actually leaning toward an ECU fault at this point, the car is an electrical mess.

 

there is a simple fix to this. just recently i had to get mine smoged and of course i wasnt ready for it. i tried the 02 patch that someone posted on here. I noticed that it works very well, no driving needed, on the 8s but on the 9 it was a no go. I drove almost 200 miles but still I wasnt ready on the monitors.

So doing more research, I did a force patch. It basically forces all your monitors to pass regardless of what. I did however change some settings to make the car look stock when passing the emissions.

I'm not on Tephra either, so it was very simple to do.
If you search for force smog patch or 02 patch, you should find it. Very helpful information in there and I no longer have to worry about anything.

 

Good to know. I will see if maybe they complete in the next week or so, its not really an imminant problem but more of an annoyance.