ECU Tuning & Fuel Management - opensource logger
jack987
07-06-2008, 03:30 AM
i have a 2005 civic and i'm looking for some 'good' opensource obdII laptop software. i have made a 'jeff interface' which is the optocoupler interface. the interface works and i have found a couple of pieces of software that work. i can read and clear codes, get some data but not all. the data that's being gotten also seems to be off just a bit. for example the mph is off by 2 mph. the o2 sensor voltage also seems high @ .660v - .700v which is indicating a rich condition but no code is being thrown and my mpg is still good @ 36.5 mpg.
what i'm looking to get from software is the IPW and correct o2 sensor voltage for tuning purposes. i'd like to lean things out some more.
if anyone has any ideas of another, inexpensive way, to do this...please pass the info on or if you know of another 'free' (opensource) software, for linux or windows, please pass that info on.
tia
Aaron_EX
07-06-2008, 11:01 AM
I dont think you can do any sort of tunning on the 7th gen civics with a some sort of EMS...or am i wrong?
trustdestruction
07-06-2008, 11:29 AM
obd2 can't be chipped/tuned, you need to convert to obd1 and get a chipped obd1 ecu
jack987
07-06-2008, 01:25 PM
ORIGINAL: trustdestruction
obd2 can't be chipped/tuned, you need to convert to obd1 and get a chipped obd1 ecu
i thought this would be an answer i'd get in a forum like this. problem is this is NOT what i'm looking to do. i don't want to chip or tune the ecu. all i want is data from it and to be able to watch what's going on with the IPW and o2 sensor info. that's it. just be able to look @ it. not make any changes. i know obdI would be the way to go to tune the systems. i don't want to do that.
what i want to do is make changes to sensors such as the o2, MAP & IAT to lean the mixture of fuel/air. i need a baseline to know where i'm @ and than make changes and be able to see the effects. no ecu changes whatsoever.
trustdestruction
07-06-2008, 01:47 PM
I don't see how you're going to lean the A/F ratio without tuning the ECU or without using an FMU.
But yea, idk of any laptop monitoring software.
jack987
07-06-2008, 02:03 PM
ORIGINAL: trustdestruction
I don't see how you're going to lean the A/F ratio without tuning the ECU or without using an FMU.
But yea, idk of any laptop monitoring software.
lean a/f by decreasing voltage going to ecu from MAP, up voltage from o2 sensor to ecu and decrease resistance from IAT. simple
trustdestruction
07-06-2008, 02:49 PM
Yea, that makes sense. I guess i wasn't looking at it right.
Anyway, I hope someone can answer your question.
ORIGINAL: jack987
...the data that"s being gotten also seems to be off just a bit. for example the mph is off by 2 mph. the o2 sensor voltage also seems high @ .660v - .700v which is indicating a rich condition but no code is being thrown and my mpg is still good @ 36.5 mpg.
1) How do you really know that the mph is off by 2 mph? For example, might your tire diameter just be non-standard? Might 2 mph lie within an acceptable margin of error?
2) I understand that 0.45V is the voltage indicating the ideal A/F ratio and that 0.66-0.7V is on the rich end. Nevertheless, are the latter voltages necessarily outside of the acceptable voltage range that would throw a CEL code? In this regard, take a look at the wide range of O2 sensor voltages that plot at the ideal A/F ratio in the diagram below (taken from a Civic service manual).
3) If 0.66-0.7V happens actually to indicate a somewhat rich A/F ratio, how do you know that the O2 sensor isn"t at fault?
Edit: Also, if the O2 sensor voltage is really an indication of running rich, why do you think that the ECU is not compensating for this condition?
http://i267.photobucket.com/albums/ii320/RonJ_HCF/picture_1155.jpg