MIL utility for O2 sensor state of health

[3Q Jay]

used diagnostic mode 2 today--no real surprises, but looking for input. engine cold, MIL out. After about 1 minute, starts flashing. 2000rpm warm toggles about 1sec intervals [passes the crude fsm 5 blinks in 10 sec test]. cruising above 2500 the on/off period is quite short. lifting foot from throttle in cruise, light on. then, decaying below 1200 or so, light off. after sitting for ~2sec at hot idle, the light is nearly continuous ON. this last part was the only thing thats troubling me. both right and left bank have similar signatures [not plotted, so may be some duty cycle differences].

Anybody try this with known bad O2s and/or new O2s?

i believe mine are factory, now at 105k and 12 years.last smog check was at 101k, residual O2 was 0.0% @ 15mph and 1663 rpm, 0.0% @25mph and 1667 rpm.

[elwesso]

I tested mine with brand new o2 sensors..... The key is to have it HOT, drive the car so its fully warmed up...

The key is how fast they switch... In 10 seconds, i got like 15 blinks but if i remember correctly they were sharp blinks..... meaning it flashed on and off fairly quick...

[RobertsnewQ]

Sounds pretty normal to me. WHen they die they get REAL lazy - ie one crossing of 4.5v (what the flash means) every second or less. Put a DVM on the line if you're worried about it.

Not hot (as wes mentioned) is not useful.

Buy one of my consult kits and you can watch the 02 sensor voltage change in real time. Beats the diag mode 2.

[3Q Jay]

got it HOT and then at idle the blinking was there.

Robert, I'd like to know more about this interface...is it to run on a laptop?also, I *really* want to know where you are at with the ecu chipping.

[RobertsnewQ]

The simple DIY consult requires a laptop and software. You can do almost everything you can do with the Official Nissan/Techtom(sp) Consult.

As for the ECUs, I can do anything you want with the 90-93 ECU - rev limits, mixtures, timing, idle, etc. etc. It's got an 8-bit processor and a soldered-in eprom. I've got several cars running on modded chips (including Wes with a custom program very soon).

The 94/95 I can do all the modifications to the original code, but I don't have the right adapter board to run it. THey use an integrated eprom/processor and a special daughterboard. I'm having trouble figuring out which daughterboard to use - there are several different kinds.

However, it's not a big deal because the two ECU types are pin-compatible and you just need to find an early active ECU if you want to modify yours. most of the code and all of the maps & tables are the same between the 93 and 94/95 ECUs.

[elwesso]

Yeah its gonna be golden.....

[3Q Jay]

hmmm, but yours is a '94, right? did you switch ecu's?

[elwesso]

I ran a 9093 ECU in my Q for a while and it was fine.

[texasoil]

I'm surprised the 2nd ECU codes are real close to 1st gen. My '94 active/TC has lots more engine parameters -- it reports out--than wife's 92 active. 94 is not too far from OBDII

[texasoil]

How about a quick info on the 'consult kit?

[RobertsnewQ]

Here's a link:

http://eccs.hybridka.com/viewtopic.php?t=108

The ECUs are pin-compatible. Just make sure you have the matching TCS/Active to your car...

[elwesso]

However the general rule is that you can run a more optioned ECU to your car that has less options...

for instance im running a TCS ECU and it works just fine..... i also ran an active ECU and again it worked fine.

[3Q Jay]

good stuff on the consult interfaces Robert!