I was wondering if I still expect to see a vf signal in the aux1 when u setup for part throttle tracking? Considering the stock o2 is no longer in the mix and the maftpro is adjusting the airfuel mix via info it get from my wideband. On my sensor page in the maftpro I just see 0.01v now in my aux1 readings. Thanks for the reply. I just wanna make sure I'm where I need to be.
vf reading when in ptt mode
- Thread starter atlpd3147
- Start date
maybe for meth inj kit 
I don't know about other people, but I still get VF readings with the stock 02 sensor gone and the ECU in permanent open loop.
If you have the stock 02 sensor disconnected, make sure you remove it completely. From what I understand, the 02 sensors can be destroyed by the hot exhaust gases when their heater element is not working. It's worse on the wideband units, but I believe it still applies to the narrowbands too. Can someone second me or correct me on this? thanks.
If you have the stock 02 sensor disconnected, make sure you remove it completely. From what I understand, the 02 sensors can be destroyed by the hot exhaust gases when their heater element is not working. It's worse on the wideband units, but I believe it still applies to the narrowbands too. Can someone second me or correct me on this? thanks.
Or you could use the purple wire to log your EGT...if I understand it correctly. But I'm seeing he same thing as well. On FTT, I think one of the other guys made a post about Vf with the narrowband O2 disconnected.
the stock o2 is completely gone. the signal wire on the harness is not cut(white wire on 88 harness) and the purple wire from the maftpro harness is connected to the vf signal wire on the ecu harness. with that setup i get no reading from my vf parameter on the maftpro sensormonitor screen. according to CRE's documentation no o2 should mean no vf signal.
You can have a VF reading of more than 0 volts in open loop, and it can also be perfectly normal. I see this in all my logs since I went permanent open loop, with no ill side effects that I know of.
Zero volts simply means that the TCCS is subtracting a lot of fuel from the base map. In the case of WOT acceleration, that portion of the map is super rich to begin with, so that's not a problem.
Given that, I'm not enamoured with the last part of the paragraph in CRE's diagram, which states that 2.5 volts is adding fuel. That is not the case. AFAIK, 2.5 volts means zero fuel correction, in all operating conditions including WOT.
Here's the far-too-indepth backgrounder:
http://www.suprasonic.org/public_html/lexusriemer/lexusnotes.html
and
http://suprasonic.org/pub/SONIC/MA70/TNSTCCS2.txt
Zero volts simply means that the TCCS is subtracting a lot of fuel from the base map. In the case of WOT acceleration, that portion of the map is super rich to begin with, so that's not a problem.
Given that, I'm not enamoured with the last part of the paragraph in CRE's diagram, which states that 2.5 volts is adding fuel. That is not the case. AFAIK, 2.5 volts means zero fuel correction, in all operating conditions including WOT.
Here's the far-too-indepth backgrounder:
http://www.suprasonic.org/public_html/lexusriemer/lexusnotes.html
and
http://suprasonic.org/pub/SONIC/MA70/TNSTCCS2.txt
JimR;1231365 said:
Incorrect. It's more complicated than that. You'll have to get all the finer details from JJ, but essentially when the O2 sensor either disconnected or the line grounded the ECU assumes a full lean condition, switches (for the most part) to the corresponding fuel map, and Vf goes to about 0v (it fluctuates a bit up to .8ish, but that represents different data than we're talking about here.). From what I know, both in experience with multiple installs and from talking with others, a reading above 0v indicates an abnormality and potentially a problem elsewhere in the system.
If this is inaccurate I'll leave it to someone far more in the know than you or I to educate us.
Now, back to my vacation! See y'all around!