Refresh Rate for new OBDLink MX+ Still Slow

[Stenman16]

I just upgraded my OBD adapter from the VeePeak to the OBDlink MX+ hoping to see an improved refresh rate.
It’s still won’t go faster than 1Hz
I’m hesitant to mess with the expert settings without advice and was hoping it would just be faster out of the box. My car is an e36 (1998) M3
I attached a screenshot…
Thanks!

[Harry]

Hello,

It looks like this is a pre-CAN car (ISO 9141-2). The PID rate one can expect for this protocol is around 6 PIDs/s. As a full set of PIDs is 4 to 5, you will see an update rate of 1 or 2 for this car. This is largely independent from the adapter used, the bottleneck is the car's bus...

To get to 2Hz (which is the max), try addressing the ECM ECU only. Other tweaks like parallel requests or tweaking adaptive timing will not work or not contribute.

- Harry

[Stenman16]

Thanks!
How do I address the “ECM ECU only?”
Also, based on my car, is the upgrade to the OBDlink MX+ a waste of money (unlikely to increase refresh rate) over the VeePeak I already have?

[Harry]

For many reasons (including their great support and competency), I like OBD Solution's devices. For your situation however, there will not be a big difference. Btw: while 1 or 2 Hz is really boring in real time, it produces nice overlays. LapTimer interpolates the data on frame level, so it will look smooth.

[Stenman16]

Thank you for the replies! I changed “ALL” to “PCM or ECM” in the “ECUs addressed” field in expert settings, but this is still what is showing up on my screenshot of status…

[Harry]

Please goto Sensor List and Refresh. Actually I'm almost sure ECU selection is supported for all protocols and not just CAN.

[Stenman16]

Ok, here are screenshots of my settings and after the sensor refresh…

[Harry]

The expert setting looks fine. The sensor information snapshot has been created before the bus type has been negotiated. Without a defined bus type, LapTimer will always show ALL because addressing is undefined. So please connect to the adapter with engine running. Once you get a connect and an update rate, re-check if ECM is shown instead of ALL.

- Harry

[Stenman16]

Now I’m not getting anything…

[Harry]

ECT, RPM, VSS, IAT, MAF, TPS (see OBD II PID Wikipedia) requests received a valid reply at least once. But the answering times are around 250ms - which is making 4 PIDs per second and 1 Hz. So besides the drop in connection you get now, this is no improvement compared to ALL. So please revert to ALL, Refresh and keep it like this. It looks like this is the best can do for the car.

- Harry