ecuflash can now remove the rear02 codes...

see my DTC disable thread in tuning subforum...

 

Has anyone tried the Megan SS Mechanical o2 Fix (CEL Fix) from Lancershop.com? I was thinking of trying it out.

 

The CEL light will pop out spontaneously, it is not on now does not mean it wont pop out in the future. The best solution is keep AP in your car or get a tune. But the funny thing is after I post the OP, it does not pop out ever since.

 

I've had a 0420 code since the day I installed my AMS HFC, about 7-8 months ago, and I'm using their CEL fix. I'm really hoping to find a solution soon so when something actually goes wrong and triggers the CEL, I'll know. My AMS spacer is on the lowest ring due to clearance issues so I'm thinking of trying the Touge Factory one with the bend in it; I'm not sure if that will help.

 

I just put in my T1R 90R catback with the resonated test pipe and got this CEL. Hope there is a fix soon. I've read a few posts on here and seems like a tune can fix thiis issue? I'm kinda confused by this, how would a tune fix it?

 

What clearance issues do you have running the AMS HFC? I have all the room in the world for my O2 sensor. With my Cobb Stage 2 tune and AMS O2 spacer installed (medium restrictor), I haven't seen a CEL since day one. Nor have I've seen a CEL when going back to the stock tune for warranty work.

 

So what is the final software fix combo that works for USDM 5 speed cars?

I was fine with the angled design UR Mini-Muffler test pipe for 2 years then this spring I would once every month get a CEL light indicating the P0420 Catalyst Efficiency Below Threshold. It seemed that if I drove the car more conservatively and cruised at lower RPM's it would have a higher chance to trigger. I also noticed once that it reported voltage being low on the rear O2 sensor location but I only saw that once.

Fast forward to the last week and my inspection is due... Well now the bloody P0420 code is being relentless and the third drive cycle is flashing that CEL like clockwork. I added in a spacer last night after cleaning up the sensor a bit with intake cleaner since it appeared a bit clogged up, still got a CEL today. I'm wondering if the sensor isn't seeing enough exhaust flow and the UR mini-muffler hole is clogged or partially blocked? When I sprayed some intake cleaner in there I could hear it trickle down into the exhaust but I remember that the hole was tiny when I last checked it. Perhaps I need to open up it up slightly and see what happens, then again if I can flash a few bits on ECUflash that would be MUCH more convenient then ripping all that apart for no good reason.

I've done searches and for whatever reason I can't find the final combo of fixes to prevent the P0420 CEL, just back and forth theories on why one car might get fixed while others don't.

 

Likely I should be bumping one of the threads in the tuning section, but it's hard to believe that nobody has found a combo that works in the last 6 months?!?

I was going to just disable the rear O2 by setting "Options 2, Bit1" from 1 down to 0 but for whatever reason it doesn't want to take "0" or "0x0" as a value and remains as 1... Oddly if I type a bunch of jibberish it changes to "0" but then claims the other values just above it changed even though they didn't. This is the latest ECUFlash as far as I know, really strange behavior here.

Update: Used the + and - key and it would toggle the bit back and forth. Still it was indicating that other bits had changed above it even thought hey hadn't, I'll test if it works today.

 

I've never had any CEL's from my testpipe/O2 dP combo. UR TP and AMS downpipe, works perfect

 

Yeah I'm betting that the threshold just got altered with the exhaust leak I have developing, I guess the heat cycles at the road courses are really torturing the ATP O2 DP in a major way.

 

Maybe, but I can say for damn sure it isn't helping the situation, lol

 

I have the spacer also and still throw this code I currently have the Ams mobil laptop I. My hands Mitch is going to send me a disable map well see if it works.

 

mate you need todo a combination of the DTC disables:

1) P0420 = bit flip for ECU_OPTIONS_2
2) P139 and P0140 are in my DTC disable thread

P0140 is new and ive only just fixed it (well a month ago now)

 

Do a battery reset for like 5 minutes, and see how that goes...