Bluetooth OBD Slowdown

Has there been any changes to the BT/OBD code stuff in the last couple of releases? I have a 2003 C5 Z06, Android LG G4 running 6.0. I have always seen a logging rate of ~5.5hz with 3 OBD parameters selected. I was messing around with the car/app the other day when I saw a new version had been released... I am only getting around 3 Hz now. Same phone hardware/software, same OBD hardware, etc etc.-- only change that I can think of is the software.

Also I did try every BT OBD "option" in the software (disable enhanced features, etc.), all of which made no difference.

Thanks!
-Aaron

None of the recent changes should have any affect on the throughput / sample rate of OBD or Bluetooth. I have seen some vehicles that seemed like they sampled slower or with more lags when the vehicle was not warmed up yet, which appeared to affect some OBD interfaces differently that others. It helped to add more data channels, thereby reducing the polling rate of any one parameter. I've also seen some of the very inexpensive clone "ELM327" devices exhibit inconsistent (and sometimes wrong) behavior.

The other thing to check is your GPS setting under the "More Options" screen... If it is set to Bluetooth, but you do not have a Bluetooth GPS device actually in use at the time, the process of searching for it can lag other Bluetooth connections like OBD. Likewise, if you had a BT GPS connected but your BT OBD interface was not plugged in, that could impact the performance of the GPS. Once the connections are established, it's fine; the Bluetooth performance degradation only happens when it's actively searching for a Bluetooth device and not being able to connect to it. This is an Android system limitation that I'd really like to find a workaround for, but in the meantime it's always good practice to turn off the Bluetooth setting for any GPS or OBD devices that are not in use at the time. You can also lower the impact of this by going to the somewhat new "Bluetooth: Advanced" section of the "More Options" screen, enabling the "Use Longer Timeouts" option and disabling "Allow Insecure Connections". However, this will make it take longer to pair with your BT devices, and there are some devices that might need insecure connections to be enabled.

Thanks for the quick, detailed response as always. For the test I had my xgps160 connected and I use the obdlink mx. I know I've done identical tests before, so I feel something else is going on here.

I'll try again with my nexus 9 tablet and see how it performs.

Well, I confirmed that the app is indeed not the problem. I tried 3.2.4 and the latest version on a Nexus 9 and the OBD speed was 5.0-5.5 Hz, depending on if the external gps (XGPS160) was being used or not. On the LG G4 still around 3.5 Hz max. I know it was faster before, so I am guessing one of these recent "security patch" updates I got on the phone is the root cause here. Might have to pick up an old Nexus 4 or 5 or something for track logging app use exclusively.

I've had enough with this G4... lots of little bugs and issues since day 1. I have a Galaxy S7 on the way. We'll see how it does in comparison.

My guess was correct. I got the S7 in today and did some testing of G4 running 5.1 and 6.0 vs S7 running 6.0. I did all tests in airplane mode, fresh factory data resets, 3 same PIDs selected/monitored.

G4 5.1: ~5.5 Hz
G4 6.0: ~3.5 Hz
S7 6.0: ~6.0 Hz

Looks like LG screwed something up with the 6.0 update....not surprising.

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I'm unfortunately experiencing a similar issue with my own new LG G5 running Android 6.0.1. It's giving me substantially lower OBD sampling rates than several other Android phones, when using the same OBD-II dongle and ECU. Thinking it was other tasks running, I put it into Airplane Mode with Bluetooth re-enabled, but got the same result. So then I rebooted it, leaving it in Airplane Mode... same result again. I turned off Airplane mode and it went up a bit for a little while, but then settled back down to the lower rate I've been getting. That's really too bad, because the wide-angle camera on this phone is awesome for motorsports.

Later tonight (hopefully), I'll be making a post with test results from a bunch of OBD-II devices and several different phones...

Cool, I look forward to seeing that data. I guess I just never expected so much variance in sampling rate between devices. If anything I didn't figure the bluetooth link would be any sort of bottleneck for an older PCM like the one in the gen 3 LSx.

Either way I'm a happy camper again. I really liked the LG G2 but the G4 was a big disappointment.

I just posted some OBD performance data here: http://www.hptuners.com/forum/showth...est-Results%29

My LG G5's Bluetooth was significantly slower than other Android devices every time, for every single Bluetooth OBD adapter I tested. I'll try to figure it out as time allows, but based on what you found, it sounds like it may be related to LG's version of Android 6.0...

Update: Good news! Early indications are that the July 26, 2016 software update for the LG G5 (Verizon models) appears to greatly improve Bluetooth performance, to a level similar to that of other Android devices. I've tested it with two OBD devices so far with good results, although it might take a minute or so to get up to the full rate. Hopefully LG will release this fix for their older phones as well...