So this weekend I installed a catless STI UP and a catted Helix DP. I already had a 3" system behind that. I also have my snorkus removed. I've been running the OTS Cobb Stage 1 map, but a did a real time reflash for Cobb Stage 2 after all the above was installed. I've been getting the P0420 code yesterday and today when I start my car the cruise light is flashing too. I can reset, but it just comes back. I cant hear any exhaust leaks. I have an '04 FXT with 67000 miles on it and only run 93 octane fuel. Anyone got any ideas? Thanks!
I get that code all the time as well....I can only associate it to being the front O2 sensor getting too much oxygen and throwing the code. I thought the AP was supposed to get rid of that as well. there is a 'fix' for it that pulls the O2 sensor out JUST enough to not trip the ECU.
P0420 means no cats or cats that are not working to OE specifications. The base map for Stage 2 disables it. Nothing is wrong with your car since its modified, its just that the ECU does not see values it likes from the REAR O2 since the cats are not to spec. All Helix catted DP's cause a P0420 on 02~05 WRX and others that have 3 cats from the factory. Most of the time STi/06+ WRX will have P0420 with that DP, rarely they wont have it. When you get a tune from Top Speed they will turn off the P0420 for you.
I thought the AP was supposed to keep that one supressed too. I reset the ECU and let the car sit for a few hours while I knocked so stuff out at the office. When I got back in the car i reflashed the Stage 2 map in realtime and then drove the 30 or so miles to the airport. No code. I'm going to check the cobb website to see if I have the most current stage 2 map. Ultimately I'd like to get a nice tune done for it so I know its right.
Funny you posted that probably about the time I was typing I want to get it tuned! :rofl: What about the cruise light flashing is that associated with that code for some reason?
"Ultimately I'd like to get a nice tune done for it so I know its right". If a few hundred bucks is not a huge issue I would get it done. You will not regret it. The drivability of my car even with AP2 was nothing close to a Siegel tune.
SUBARU was kind enough to disable the cruise and make the light blink so that it would ANNOY THE EVER LIVING SHIT out of people so they would actually bring the car in for service. I thank SUBARU for this, I have more biz because of it. Takes two consecutive drive cycles for the P0420 to set.
Also make sure you are flashing the stage 2 base map as well. Not sure if the RT map will disable codes....
^^^^ Werd! I've read "stage 2 base map" multiple times and it took you saying that for it to click in my head. Guess I've got two things to do when i get home, connect my little green connectors and call SS for a tune! :wavey:
Not sure what year or how it flashes, but don't forget the other little thing you plug in...for mine, I have to connect the 2 green plugs and then take a clear plug and plug it into another clear plug under the dash.
Fly by wire only requires the green connectors. Only the 02~05 WRX's need the other connector do-dad-thingy-mojobber.