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lsu 4.9 sensor dead in a week need to figure out why

Posted: Thu Mar 03, 2016 3:21 am
by fuzzysig
I have MTX-L unit that came with 4.2 sensor
that sensor lasted just barely over a year
it started reading wrong afr and then throwing E8 all the time
and only works at very light throttle any time I step on it it throws E8

so I went and bought a 4.9 sensor and changed the firmware to 4.9 sensor and latest firmware
all other settings are default

its installed on integra in stock O2 location before the cat
was wired to the thermostat housing( which is the ecu ground point)
and relay to the battery and ignition trigger
now its wired to the ECU harness directly suggested on PGMFI forum for less fluctuation
the 4.9 sensor worked fine for a week and 3 days ago I drove about 10 minutes and watched it slowly creep up to 22.4 afr and it now stays there
calibrating doesn't help
I changed to another mtx-l unit and its same thing
the only time it moves is when I decelerate in gear and then release the gear letting the RPMs fall to idle
then the AFR drops to normal for a few seconds and jumps back to 22.4

yesterday I turned the car off and left ignition on after about 5 minutes the Afr slowly went from 22.4 to 17.4 afr and stayed there

I don't know enough about widebands or controllers and couldn't find anything when I searched online

I would like to know what those symptomps tell you guys is it just a bad sensor or something else is wrong?

Re: lsu 4.9 sensor dead in a week need to figure out why

Posted: Sun Mar 06, 2016 3:41 am
by Hentai
I would suspect the controller isnt coping well with the changes in temp at the o2 and ending up killing the sensor~

Personally I suggest dumping that wideband controller for a better system

Re: lsu 4.9 sensor dead in a week need to figure out why

Posted: Sun Mar 06, 2016 4:10 am
by fuzzysig
I need one with serial or better yet usb im using it with neptune for obd1 honda ecu
And i need a gauge as well its permanent install in my cluster

Should i get a gauge controller built in or gauge with separate controller?
the new aem x type seems nice but i find no reviews about it yet

And ghostaccord on HT said the new lc-2 is a redesigned controller but someone here said its same controller as mtx-l
So i dont know what to get

Re: lsu 4.9 sensor dead in a week need to figure out why

Posted: Sun Mar 06, 2016 5:28 am
by Hentai
fuzzysig wrote:I need one with serial or better yet usb im using it with neptune for obd1 honda ecu
And i need a gauge as well its permanent install in my cluster

Should i get a gauge controller built in or gauge with separate controller?
the new aem x type seems nice but i find no reviews about it yet

And ghostaccord on HT said the new lc-2 is a redesigned controller but someone here said its same controller as mtx-l
So i dont know what to get
you are unlikely to find any usb, and the most of the serial ones I wouldnt trust.

There is only one I am gonna recommend and its the ecm based controller.
I don't know whats required for your serial output, if its to bring into the computer or trying to get digital coms to get around voltage offsets, but a proper controller will allow you fix for the offset durning warmup.

Re: lsu 4.9 sensor dead in a week need to figure out why

Posted: Sun Mar 06, 2016 7:41 am
by fuzzysig
Honda ecu stock o2 input is a pain in the ass. its an algorithm from 0 to around 3.67 volts depending on ecu
mtx-l fluctuates sometimes close to 2.0 afr while gauge is solid no matter what I do
with serial input its much easier and cleaner also
Neptune supports a lot of the serial widebands
but most of them are innovate lol

what about 14point7 some of them list USB as a feature.
and the new AEM type x also has a usb feature

Re: lsu 4.9 sensor dead in a week need to figure out why

Posted: Mon Mar 07, 2016 1:41 am
by DelSolid
fuzzysig wrote:and the new AEM type x also has a usb feature
Just a correction here. The X-Series does NOT have a USB output. Along with the traditional analog output, it has CAN and a RS232 output but no USB output.

Re: lsu 4.9 sensor dead in a week need to figure out why

Posted: Tue Mar 08, 2016 5:57 am
by fuzzysig
what about failsafe AEM gauge?
it says pc setup through USB I'm assuming that also means direct logging?
seems like it also has boost/vacuum and rpm input and some other inputs from engine

what would you guys recommend to replace my suspicious MTX-L unit?
i need something rather quickly i want to drive the car lol and still need to drive an hour and a half to the dyno

Re: lsu 4.9 sensor dead in a week need to figure out why

Posted: Tue Mar 08, 2016 6:45 am
by DelSolid
fuzzysig wrote:what about failsafe AEM gauge?
it says pc setup through USB I'm assuming that also means direct logging?
seems like it also has boost/vacuum and rpm input and some other inputs from engine
The AEM Wideband Failsafe has an internal logger that records AFR and boost and RPM (if connected) and you download the log through the USB port and view it in a separate program. It logs all the time, no PC needed to log, just to download it. It uses the Bosch LSU4.2 sensor and the Bosch CJ125 chipset.

Re: lsu 4.9 sensor dead in a week need to figure out why

Posted: Fri Mar 11, 2016 6:02 am
by fuzzysig
So which ones would you guys recommend that have serial output for datalogging?

Re: lsu 4.9 sensor dead in a week need to figure out why

Posted: Thu Mar 31, 2016 10:56 pm
by Hentai
why don't you fix the input to read 5v's it seems like this is a known issue in the honda world and they have a way around that input and to fix it.
or perhaps move it to a different input and make sure the tuning software can let you do that.