Not looked at logs on phone yet. The DCT variants are not usually present except for torque related maps so best to change AT and MT to test as you are. Disable cold start I don't know what is being altered but it will not be overwriting these as they were discovered after that option. It may be they are not used in the same way/for as long but they will not be physically overwritten.
DIY tuning
- Thread starter Sbrach
- Start date
I suspect it is mainly Vanos related and probably ignition timing. Honestly, these cars go closed loop so quickly after start that I'm not sure this is really necessary in this climate. I've never had a fail to start, just an unstable idle for a few seconds before it goes closed loop and a slightly longer crank.
The fast closed loop is good, how long are you finding it takes in various temperatures? Interest of course is virtual flex fuel. The previous ethanol value would be stored now I've worked out how to write to EEPROM, so cold start would be fine if the previous ethanol estimate was fine and we blend the correct cold start tables. But I really need it to be closed loop very soon after a refuelling event, as quick as a potentially different mix hits the injectors anyway.
Your log looks like you have STFT 10s after starting, so it looks like then it is closed loop. I don't know if the STFT going to about +6% between 10s and 60s after a start is typical on gasoline? Interesting looking at valve lift req and throttle. Looks like it is starting with valvetronic actively controlled, but VANOS not, backing up earlier thoughts about a motor vs oil pressure control.
New cold start logs with noise reduction unchecked.
Thought I had logged intake and exhaust vanos yesterday and today but see now that I had logged intake act and intake req by mistake. I’ll fix that tomorrow.
https://datazap.me/u/sbrach/rev43-cold-start-test-2?log=0&data=6-9-13-14-15-16-17-20-34&solo=13
Thought I had logged intake and exhaust vanos yesterday and today but see now that I had logged intake act and intake req by mistake. I’ll fix that tomorrow.
https://datazap.me/u/sbrach/rev43-cold-start-test-2?log=0&data=6-9-13-14-15-16-17-20-34&solo=13
Turned Cold Start Noise Reduction back on, Logged various load/rpms to get fuel scalar dialed in better for E54, increased post start fuel tables a bit more and logged another cold start at 8C ambient. STFT is much better, had a longish crank, about 2sec, so I'll try increasing the start table a bit more. Closed loop starts 5sec after start, is that good enough for Virtual Flex Fuel? I glossed over that in your previous post, I thought your work was using a ethanol content sensor. The newer GM stuff is virtual Flex Fuel as well, correct?
https://datazap.me/u/sbrach/rev45-cold-start?log=0&data=0-9-13-14-15-16-17-34&solo=9-13-15
https://datazap.me/u/sbrach/rev45-cold-start?log=0&data=0-9-13-14-15-16-17-34&solo=9-13-15
Nice to know the afterstart tables are having an effect. Thanks for testing.
OEMs keep switching between virtual flex fuel and a sensor. I keep doing the same
but seriously I think I would like to do both but have the sensor version coded. I think 5 seconds if plenty fast enough as it would take at least that long to get a new mix from the tank to hit the injectors. I'm juggling new features vs finishing existing stuff.Nice to know the afterstart tables are having an effect. Thanks for testing.
OEMs keep switching between virtual flex fuel and a sensor. I keep doing the same
After filling my tank and watching the gauge, it takes at least a few minutes into my drive before it starts to go up on the gauge. I'm sure it would be faster if the tank was very close to empty, but these tests were with at least > 1/4 tank.
Logged a warm start this afternoon, coolant at 88C, ambient at 25C. Took just under 70s for STFT to show a change. Lambda was rock steady at 14.97 nearly the entire time though.
Edit:
Added log https://datazap.me/u/sbrach/warm-start-test?log=0&data=0-9-13-14-15-16-17-20-21-34&solo=9-13-15
Edit:
Added log https://datazap.me/u/sbrach/warm-start-test?log=0&data=0-9-13-14-15-16-17-20-21-34&solo=9-13-15
Last edited:
https://datazap.me/u/sbrach/rev49?log=0&data=4-5-14-17-24-25-26-27-28-29-30-32&solo=30-32&zoom=0-113
Latest log. Switched to N20 plugs and first log had big corrections. Might have been a fluke.
Not sure why my boost request has the weird dip in it. It’s always there. I’m over boost target but under load target so maybe that is the cause of the corrections?
Latest log. Switched to N20 plugs and first log had big corrections. Might have been a fluke.
Not sure why my boost request has the weird dip in it. It’s always there. I’m over boost target but under load target so maybe that is the cause of the corrections?
https://datazap.me/u/sbrach/jed-3?log=1&data=3-4-12
Cannot figure out this dip in boost request in lower gears. It goes away 4th and up.
Cannot figure out this dip in boost request in lower gears. It goes away 4th and up.
Overboost? seems to drop target when boost goes over. Once boost is below target, it will raise target again.