Can't help you with the PID for knock itself but the Mode 21 PID for timing retard is known along with its equation. You could use that as a proxy since anytime there is knock retard there is knock presumably.

If you do come across the answer would you let me know? Have been playing around with reverse engineering fuel and timing tables and having knock values would add another dimension of interest.

I found issues logging in OBD2 because of the sampling frequency, limit of 5 PID's per second makes the results of limited value.

Switched over to logging with an Emanage Ultimate its sampling frequency is about 50Hz and as a bonus it can log knock sensor output directly.

PS. Maybe you could sniff the knock PID out of a Techstream clone?

PPS. It would be really cool to get PID's for VVT.

 

Cool, thanks! So, technically I could scan that one PID at 5 Hz on the OBDII port. But, I think knock retard would last a lot longer than 200ms right? I'm looking for some additional safeguards while tuning the FIC. I am not going to the Megasquirt right away. Techstream apparently interrogates the CAN BUS so it should have a faster polling rate. I suppose the only catch would be that it would be tough to feed anything from the Techsream into the FIC AI for data logging. So I would be looking at it in two places.

Any idea what the structure of the call is in Mode 21? Should be something like IGN RETARD or TIME RET.... This particular one is not listed in the Taco or Prius forums.

 

The command is 21B2 and the response should be 61B2xxyy.

xx and yy are hexadecimals. The formula to decode the response is:

Knock Retard = (xx * 256 + yy) * 0.03125 – 64

The source for this is here: http://www.mthrfknwin.com/diagnostic-port-obd2-detail-manufacturer-specific-pids/

In principle you should be able to add this PID to Torque Pro on your Android device through a CSV datasheet. I haven't actually tried this, so I'd be interested in how it turns out if you try it.

By the way if you have $50, a Bosch donut style knock sensor, and a 3.5mm jack, you can monitor knock on most windows computers with this software:

https://gumroad.com/l/qaqv#

Check out the tutorial at the bottom.

 

Great find. I created the custom PID. I'll try it out tomorrow. I'm not really sure about that scaling though. Will report back, thanks!

 

These guys do have Toyota specific PIDs including missfire by cylinder number, etc. Might be worthwhile to talk to them.

https://play.google.com/store/apps/details?id=com.obd2.elmscantoyota

 

Ha ha now they've got my $5.71 and I will be trying it on the way to work.

PS. You realize these are Russian hackers and they will take over the car and send all of your datalogs to wikileaks, right?

PPS: No collusion! No collusion! http://elmscansoft.com/

 

Earlier I stopped myself from saying "If it’s what you say I love it..." because of potential implications.

Anyway this is indeed what it claims to be. The proprietary Toyota PID's are all there, for a number of different Toyota architectures.

The user interface and operability are quirky but nothing insurmountable for someone intent on making use of the app.

Having evaluated it, I have removed it from my devices and destroyed all its data and related files, just to be safe.

The real question for a hacker would be how to hack this and make use of its data in other contexts. Anyone?