Mark2009

Been playing a little bit with an Android smartphone app called "Torque" (I have no association or affiliation or monetary interest). With a separate bluetooth OBD-II dongle (~ $15 on ePray, ~ $90 for a quality unit) it will read PCM codes and PIDs and will ... drumroll please ... data log that PID data (RPM, cat temp, MAP, MAF, etc, etc,).

You have to fiddle with it a bit, instructions mostly not included, and the Chinese version of the ELM 327 dongles might be persnickity, but here's what I got after tinkering a bit today (smartphone data exported via eMail as CSV into Excel spreadsheet):

RPM & Cat Temp on left:


Temperature in F and Speed in MPH on left:



It also logs GPS data that can be exported into Google Earth, which could be used as a very crude track map (dunno if the OBD-II data can be displayed/overlaid on the Google Earth platform).

With the smartphone properly mounted, it can also record video with some OBD-II data overlaid on that video. At this time I don't have the mount handy to try that out.

The smartphone app is about $5. From what I read you do need the ELM 327 version OBD-II adapter (or at least that one is supposed to be the simplest to set up). One thing that tripped me up at first is that you have to pair the phone with the bluetooth dongle as a bluetooth device, then fire up the app (which will then find the bluetooth OBD-II thingie).

One downside is that my car does not like having a code reader (OBD-II) device plugged in during multiple starts -- it will throw the odd code. If I erase the code and remove the code reader (bluetooth dongle, whatever) then all is fine. This happened today with the bluetooth OBD-II dongle and with an additional generic code reader I have. YMMV.

DaOtherOne

That's pretty cool!

Javvy

The link below is for one of those loggers.
I think its ideal to see whats happening.


http://www.scantool.net/obdlink-mx.html?from=Torque

Mark2009

More fiddling with this. I see that the track rats are aware of this app and others in the road racing sections, but following up for those of us that don't get there too often.

There is an Android add-on for Torque called Track Recorder. It allows your smartphone to record video and also grabs OBD-II data to correlate to that video. During setup you can select what data you want to record along with the video (assuming you have an OBD-II Bluetooth dongle like that mentioned in the OP). When you replay that video on your smartphone, you get a text display of the data on top of the video.

But when you go further third-party, you can get cheap software that will allow post processing to overlay the data onto the video in a cooler format. Witness the clip below (I'm geeked out on non-stoichiometric air fuel ratio in this instance):






This version of RaceRender is free. If you want clips longer than 3 minutes or cooler gauges then you have to pay. I have no affiliation or gainful interest in any of these products nor anyone associated with them. Total outlay to make the above video is about $20. Text overlays via Windows Live Movie Maker (free bundle with Windoze).

Turbooo2u

Can this read A/F ratios thru the OBD 2 port? Very interesting.

Mark2009

It reads what is commanded by the PCM based upon its programming (which is what is shown in the video), not what the actual reading is. You can read the O2 sensor value (voltage) from the OBD-II port, but that is narrowband and won't really tell you if your AFR is, say, 12.4:1.

I was just curious to monitor what was going on when the PCM went out of closed loop, which it does at some % throttle position (which I obviously exceeded when I mashed on it a bit in the video). Somebody like Jim @ Halltech knows a lot about this stuff, I'm just dabbling.

Michael_D

Wow, your car is very quiet. So that's what a stock Z06 sounds and drives like... No surging and bucking, blubbering, angry visceral acceleration... I bet you can even hear your radio! That video was actually quite relaxing... I think I need to buy a new vette and leave it stock. Shiit, I'm not getting old anymore, I AM OLD! I need a kleenex..

wolf8218

Want to trade Michael?

Mark2009

I've done the cam/headers/intake/broken rockers/broken differential thing long long ago in a BBC galaxy far far away (Big Block Chevy).... no interest in a repeat on a street car

Surviving 67

Will it log knock and timing?

Mark2009

I believe it will do timing... basically it will log whatever is available at the OBD-II port like most generic scan tools. A bit of reading shows that the knock sensor is not always easy to log, even on the high end scan/log/tune software.