Hey gurus,

I posted a note in another thread, but thought that a proper post would get more exposure and be easier for other people to find if they had a similar question.

Using ECUFlash, I changed ECU Options #2, second last bit (bit.1) to 0. I removed the sensor from the exhaust stream and capped and covered it, I didn't remove it completely (mostly because I don't know how). After nearly 700 KMs, I got a CEL, and now even after clearing the code it pops up about once a day. The CEL code itself is P0140.

I'm looking for some input into how I messed this up. I have a test pipe with a spacer to decrease likelihood of CELs, but I thought that this would be a more permanent solution. Is it because I didn't remove it completely, could that have resulted in the P0140? I know that this "fix" turns the heater off, so I made sure to remove it from the exhaust to avoid damage. I'd prefer to have to tied up under the car so that I can throw it back in if necessary, but if the only solution is to remove it, let me know.

Thanks in advance...

 

Well, since nobody offered any suggestions, I unplugged the Rear O2 Sensor Harness.

In case anyone else is having issues or wants to do this, I've attached a diagram. The sensor harness is under the passenger seat. If you move it all the way back, there is a flap cut in the carpet that you can see the grommet that the O2 wire goes through. The harness is visible there.

I'll report back if the CEL ever comes on again.

 

It feels like I'm talking to myself. Creepy.

Anyway, I just got another CEL. Something isn't right. I'll recheck that I flashed correctly, but I am pretty sure that I did.

ECU Options #2, Second last bit --> 0 (bit.1), right?

 

Nope, you don't disable it by just changing the bit in the ECU Options itself. You need to change some figures on another map which will in turn change the ECU Option bit. If you use gunzo's map this is already done.

 

yeah just change the bit.1 to 0 in ECU Options 2 periphey bits.

what was the DTC code?

 

is it P0140 both times?

email me the rom ill dbl check you have done it right

 

Oops, nevermind, I guess I was doing it the old way using this address:

<table name="O2 CEL Fix" category="Misc" address="500a2" type="1D" level="1" scaling="Hex8"/>

But I just confirmed that chaning the ECU Option actually changed the figures in this address too.

 

Rear O2 disable works just fine for me!

 

What the hell...

Ok, I'll confirm the latest was P0140 and I'll send you the ROM tephra. Thanks for looking into it.

Sigh.


EDIT: Ok, code is again P0140. I've sent the ROM to tephra (thanks again), hopefully something obvious sticks out?

 

to those ppl that it works for - post up your romid AND whether you left the sensor IN or OUT

 

Tephra is heater also included in Option bits?

Shorted heater circuit in O2 sensor migth be the reason. (Usually requires replacement of heater circuit fuse in fuse block also)

 

yes as far as I can tell.

i have removed my rear 02 sensor (bar the wideband analogue connection) and receive no CEL's

 

It seems like the JDM, EDM, & AUSDM are already disabled (bit 0) from the factory. The ones having problems are the USDMs where they have to change the ECU Option.

 

your looking at the wrong bit...

my AUDM roms have the bit enabled...

 

end EDM too, but bit works well for EDM too!