igzy

iTrader: (18)

Sorry don't mean to annoy you too much with my probs Trying to troubleshoot the O2 sensor code. After replacing loads of things, I suspect I have a problem with fuel system. So would need to know if I am running rich (leaking injector or fuel pressure regulator) or lean (clogged injectors). If anyone knows how to read this, could you please help me confirm my suspicion. I would need to know if the bank 1 (B1) is running lean or rich. My guess is lean, just need someone to confirm it. Printout has the following info on it:

DTC RESULTS

HO2S2(B1)
[P0140]

FUEL SYS-B1 Mode4
FUEL SYS-B2 Mode4
CAL/LD VALUE 51%
COOLANT TEMP 84%
L-FUEL TRM-B1 101%
L-FUEL TRM-B2 100%
S-FUEL TRM-B1 97%
S-FUEL TRM-B2 104%
ENGINE SPEED 2337 RPM
VEHICL SPEED 106 km/h
ABSOL TH-P/S 11.55%
B/FUEL SCHEDL 6.4 msec
INT/A TEMP SE 29 C

Thanks again

igzy

iTrader: (18)

C'mon guys, I'm someone here knows how to read this...

These are the conditions under which the code P0140 got tripped. I am trying to understand what TRM readings mean, i.e. if the mixture was reach or lean and that is why the sensor set the code... It will help me diagnose the problem...

spirilis

iTrader: (2)

I think that's similar to the data you get with a standard OBD-II reader. Except they don't get the B/FUEL SCHEDL, and I have no idea what 6.4msec would be in the grand scheme of things.

In either case, I have no idea if it's possible to take this one printout, which appears to be a single snapshot in time, and correlate it with what you're saying. I'd imagine you'd have to view those settings over a lot of different samples in different situations to determine that.

But I'm not a certified auto technician.

igzy

iTrader: (18)

Thanks spirilis, I thought that those TRM % levels are able to tell me something, I am thinking that 97% on B1 is out of the expected range and that is why the code got tripped.

Based on the research I've done, after replacing the sensor, if that does not help, next thing to look at is the fuel/air/vacuum/MAF. I changed the MAF, I don't have vacuum leaks, so I am looking if the injector(s) are clogged or leaking, hence the question I have poured some injector cleaner in and will see if that will help in case it is clogged. I don't know if one is leaking (causing reach mixture) so I am hoping that someone can decode what the print-out means, if anything

spirilis

iTrader: (2)

I'm not 100% sure if this is compatible but my OBD-II scantool (Auterra OBD-II Dyno-Scan for PalmOS) reports Long and Short Term Fuel Trim in values of -25% to 25%. Maybe that's equivalent to 75%-125% by the Consult-II's gauge?

If that's the case, a reading of 97% for short term fuel trim (which bounces back and forth very very often--as often as the O2 sensors do, in fact, which leads me to believe that Short Term Fuel Trim is basically reporting the ECU's actual response to the O2S's signal) isn't bad at all. If it stayed at the extreme, eg at 75%, frequently then you'd definitely have a problem.


Also, did you say that's Sensor 2 in Bank 1? Sensor 2 is the catalyst sensor (Sensor 1 is the primary O2S which influences short-term fuel trim). That would indicate either a problem with the precat, or it could be an issue where the fuel/air ratio is bouncing around too fast (and tricking the ECU into thinking the catalyst is bad since sensor 2's reading may start to bounce around quickly under those conditions too)

igzy

iTrader: (18)

Yes, that is my understanding too, that B1 sensor 2 (one that threw the code) is just a monitoring sensor of the mixture levels and that sensor 1 actually influences the trim. Now, I don't have pre-cats (have Y upgrade) so their failure would be out of consideration, so why would the ratio be bouncing around? I had also verified the fuel pressure regulator to be good... I think I have nailed it down to injectors...