I have been chasing a miss fire on boost, like a hard cut, at 3psi each time.
The car will rev way past up to redline on part throttle.
Knock count increases when it happens. I’ve pulled timing way back, increased fuel at that point on map for testing. 3psi… no more.
I have knock action disabled. I have CEL set to not display knock.
Yet, at 3psi, even with overboost protection off, I get a CEL and the car increases knock count, and kills the spark.
I set the knock action to 5k etc, still cuts out even with it disabled, at 3000rpm, knock and cut.
I’ll upload the map in the morning, but I cannot find what on earth would make this happen.
Car VR5, DSG, v3.056 firmware. Issue has persisted through several firmwares. 054, 055 etc.
publish the log and the base ma0
1 Like
To explain the log. I had the laptop running all evening while running tests, and general driving.
There are numerous stop starts. However, towards the end of the night, I set the knock strategy to cut individual cylinders. (Near the end of the log)
I changed fuelling and timing several times to see if I had a map issue over the 2 hours.
I ran this car last week with a 2psi spring in the actuator, and it ran perfectly with no cuts or problems.
On a side note, this log shows the manual DSG mode, and the manual inputs to the system, the box doesn’t change on demand.
Was there any movement on this bug / issue? Should I set the knock actions to zero for now. ?
I looked at the log.
What I can see you loose sometimes sync at low RPMs.
Can you indicate the cut moments in the log (time).
When you increase boost and there are cuts, the typical reason is weak spark.
Try for test increase the dwell time.
1 Like
Also make sure your base timing is correct. If you have knock and broken spark plugs the issue can be connected to too much advanced timing.
Timing is minimal, boost is minimal. I’ve run 2psi with zero issues, I pulled the timing back during testing.
Either way, I turn the knock off on the settings, and the car still applies knock detection.
Surely it should ignore knock action if that’s set to off.
I’ll do a specific run, and log it this week. It happens every time so we can isolate easily.
Loopyonion:
Yet, at 3psi, even with overboost protection off, I get a CEL and the car increases knock count, and kills the spark.
Knock detection and knock action are two separate things. Knock detection is a strategy that detects the knock based on gain frequency and sensor cylinder asignement. When the knock is detected the knock count is increased. If the spark plugs are broken it looks like there was a knock.
The knock action is a strategy that is activated when the knock detection detects the knock. So if you disable knock action, the knock detaction works normally but nothin happens when the knock occurs.
Looking at the log the other week, there was no stand out cylinder.
I’ll re log with a few clean pulls. See if I can isolate anything.
1 Like
