Bosch "Flat Response" Knock/Setup Verification

[Anfurnyy]

Ive swapped out my 1g dsm OEM knock sensor for a Bosch wideband or flat response (part number 261231006)

Ive got it configured as a 7k hz narrowband channel, and ive got the gain lowered to 50 and it still seems to be putting out really high knock levels in the midrange causing it to pull timing.

I have soldered a jumper to and from the correct pins, and verified that there is no polarity on the sensor. 

its a 6 bolt 4g63, with the balance shafts removed, sensor is torqued into the OEM knock sensor location as well and connected via the factory knock harness. 

Could i be doing something wrong or do I just have a really noisy engine, or am i actually getting knock or is my ignition table too aggressive in the midrange? I tried to make it pretty soft as i was just trying to get fueling dialed in. 

Any help or advice is appreciated. 

 

[Øyvind Ryeng]

I'm probably running a different sensor (OEM Bosch/Volvo from 1991), and with a gain channel value of "12" I'm easily seeing rational numbers over the whole range. On my setup the engine noise increases rapidly from 4000 RPM on up, but looking at the plugs it's not detonating as far as I can see. Cylinder knock level gain for cylinder 1 -> 4: 1.08, 0.88, 0.88, 1.00. This is my first time setting up knock sensing, and I was impressed with how smoothly everything went by following the instructions in the help file.

[Anfurnyy]

 

6 minutes ago, Øyvind Ryeng said:

I'm probably running a different sensor (OEM Bosch/Volvo from 1991), and with a gain channel value of "12" I'm easily seeing rational numbers over the whole range. On my setup the engine noise increases rapidly from 4000 RPM on up, but looking at the plugs it's not detonating as far as I can see. Cylinder knock level gain for cylinder 1 -> 4: 1.08, 0.88, 0.88, 1.00. This is my first time setting up knock sensing, and I was impressed with how smoothly everything went by following the instructions in the help file.

I'll check out the help file and see if that helps fix things. I know without the balance shafts these cars can vibrate a bit more. Hopefully I can get this squared away

[Anfurnyy]

9 hours ago, Øyvind Ryeng said:

I'm probably running a different sensor (OEM Bosch/Volvo from 1991), and with a gain channel value of "12" I'm easily seeing rational numbers over the whole range. On my setup the engine noise increases rapidly from 4000 RPM on up, but looking at the plugs it's not detonating as far as I can see. Cylinder knock level gain for cylinder 1 -> 4: 1.08, 0.88, 0.88, 1.00. This is my first time setting up knock sensing, and I was impressed with how smoothly everything went by following the instructions in the help file.

So I think I might have gotten it figured out after reading the Help files. I might have had my timing set too low and it was actually retarded enough that the knock window was happening in the next ignition cycle? I'm not 100% sure on that but I advanced it enough to keep the knock window before top dead center instead of after? Or maybe the smarter move would have been to reduce the knock window from 10° to around 5°? 

[Øyvind Ryeng]

The "window start" parameter follows your ignition timing! My window start value of "10" means, in my case, that the ECU starts listening for knock during full-throttle, full-load at around 9 degrees BTDC with ignition timing in those cells at 19 degrees. It keeps it's ears open until 51 degrees ATDC, after which knock detection is finished for that cylinder that engine cycle.

[Adamw]

16 hours ago, Anfurnyy said:

Ive got it configured as a 7k hz narrowband channel, and ive got the gain lowered to 50

6K narrow works best on my Evo7.  Gain is typically <5.

[Anfurnyy]

2 hours ago, Adamw said:

6K narrow works best on my Evo7.  Gain is typically <5.

I might have to give that a go. When I did the math for the frequency it showed something like 6.8khz so I went with 7.