Datalog Timing pull ,most likely culprit?
- Thread starter rev210
- Start date
2020-10-09 12_26_25 I8A0S FF DavidHollands 35bar PS2 twins E60_93oct AIC6 PI v0.06_FF.mhd.csv
2020-10-04 16_20_22 I8A0S FF DavidHollands 35bar PS2 twins E60_93oct AIC6 PI v0.06_FF.mhd.csv
2020-09-23 14_56_44 I8A0S FF DavidHollands 35bar PS2 twins E60_93oct AIC6 PI v0.05_FF.mhd.csv
2020-09-12 17_15_06 I8A0S FF DavidHollands 35bar PS2 twins E60_93oct AIC6 PI v0.05_FF.mhd.csv
similar corrections to yours and I've changed everything ...no dice. its not tune or octane related either ....still getting some pretty major correction. even changed engine mounts thinking there was too much flex or vibration but that wasn't it either. Now starting to think its related to the auto trans or driveline /driveshaft causing knock sensors to freak out. engine runs smooth , no noise , oil is clean and it makes power but I just can't figure out why ive been getting these corrections all season long
This appears to be an issue with the N54 engine that seems hard to determine the cause. I have experienced multiple timing corrections with my engine whether I am running 100% E85 or 93 PULP as demonstrated in the datalogs below.
100% E85
https://datazap.me/u/coupes44/wedge...8-9-10-11-20&trim=0&tmin=2791.24&tmax=2809.41
93 PULP
https://datazap.me/u/coupes44/datal...7-8-9-10-11-21&trim=0&tmin=891.11&tmax=910.32
However, when I add a bottle of octane booster to the 93 PULP, the timing corrections disappear.
https://datazap.me/u/coupes44/test-...8-9-10-11-20&trim=0&tmin=3491.26&tmax=3508.16
Why? If the knock is from a mechanical noise, how does adding octane booster stop this? Why didn't running 100% E85 stop the timing corrections, if the octane booster does? Are the timing corrections resulting from a false knock and if so, what is causing this. Plenty of questions but no answers
100% E85
https://datazap.me/u/coupes44/wedge...8-9-10-11-20&trim=0&tmin=2791.24&tmax=2809.41
93 PULP
https://datazap.me/u/coupes44/datal...7-8-9-10-11-21&trim=0&tmin=891.11&tmax=910.32
However, when I add a bottle of octane booster to the 93 PULP, the timing corrections disappear.
https://datazap.me/u/coupes44/test-...8-9-10-11-20&trim=0&tmin=3491.26&tmax=3508.16
Why? If the knock is from a mechanical noise, how does adding octane booster stop this? Why didn't running 100% E85 stop the timing corrections, if the octane booster does? Are the timing corrections resulting from a false knock and if so, what is causing this. Plenty of questions but no answers
Interesting. Did not review your logs, pita on phone. Ethanol is more prone to preignition so that is a possibility. Its knock resistance might be preventing that from escalating to heavy knock but enough to be picked up.
I assume you tried gutting the timing as a first check?
Try varying the AFR. Preignition likes an AFR "window" and gut the timing curve (separate tests). If either of those work its combustion related - add water injection.
I assume you tried gutting the timing as a first check?
Try varying the AFR. Preignition likes an AFR "window" and gut the timing curve (separate tests). If either of those work its combustion related - add water injection.
I've also been having the same issue with my car. What strikes me as odd is the way the corrections appear though; looking at some of my older logs, when knock happened, the car would pull timing across many or all cylinders at roughly the same time. Now, similarly to some of @rev210's logs, the timing pulls seem to happen on only a few cylinders at a time, and often staggered from each other. Severity of the corrections also seems to vary from pull to pull, as well as which cylinders they appear on.
I am having a very similar issue, I have been pulling hair out over it. I started with spark plug gaps, redid all of them and changed the gap, it helped. Then I added CP water/methanol injection. This helped slightly, I then added duel water methanol injection nozzles, this helped some more. I then changed the nozzles to 2x 11cfm nozzles. This helped even more but still the corrections persisted.
So then I replaced all my coils with brand new delphi coils! This helped some more but still not fixed....So then I went direct port methanol injection and this helped allot but still not perfect. I then decided to try some water in the mix as I was running 100% methanol and this helped ALLOT!! I went with a 70/30 mix 70 being methanol and 30 water.
Now I only seem to get timing pulls in cylinder 4 but they seem to be quite heavy on some pulls, every other cylinder is just zeros across the chart but cylinder 4 keeps giving me the finger. I have checked the plugs, checked for a leaky injector by leaving the car over night and checking the plugs...no fuel smells and no wet plugs. So now I have ordered new injector seals as my injectors have been pulled out without replacing the seals or the retention ring thingies before so I'm thinking that could be the problem. If that doesn't sort the issue out then I am going to replace injector number 4 (they are all revision 12 injectors but I have already had to replace injector number 2 as it was leaking). so I am thinking injector 4 might have a funky spray pattern. If replacing the injector itself doesn't help then I am at a loss.
So then I replaced all my coils with brand new delphi coils! This helped some more but still not fixed....So then I went direct port methanol injection and this helped allot but still not perfect. I then decided to try some water in the mix as I was running 100% methanol and this helped ALLOT!! I went with a 70/30 mix 70 being methanol and 30 water.
Now I only seem to get timing pulls in cylinder 4 but they seem to be quite heavy on some pulls, every other cylinder is just zeros across the chart but cylinder 4 keeps giving me the finger. I have checked the plugs, checked for a leaky injector by leaving the car over night and checking the plugs...no fuel smells and no wet plugs. So now I have ordered new injector seals as my injectors have been pulled out without replacing the seals or the retention ring thingies before so I'm thinking that could be the problem. If that doesn't sort the issue out then I am going to replace injector number 4 (they are all revision 12 injectors but I have already had to replace injector number 2 as it was leaking). so I am thinking injector 4 might have a funky spray pattern. If replacing the injector itself doesn't help then I am at a loss.
Water seems often overlooked at how good it is at stabilising combustion.
Here's what I've done and replaced so far:
Injectors
Coils
Plugs
Hpfp
Er chare pipe due to broken tab at c clip
Meth pump
Cleaned and replaced meth injectors...flow and spray pattern are good.
Engine mounts
Tried boostane
Tried an e50 ethanol mix using e98 and 94 pump gas
Have not enjoyed the car all season trying to chase these corrections down although I did run a 5.91sec 100-200 at one point
Now concerned that if I dump more money into rebuilding the trans and tq converter that ill still be in the same boat come next spring.
Injectors
Coils
Plugs
Hpfp
Er chare pipe due to broken tab at c clip
Meth pump
Cleaned and replaced meth injectors...flow and spray pattern are good.
Engine mounts
Tried boostane
Tried an e50 ethanol mix using e98 and 94 pump gas
Have not enjoyed the car all season trying to chase these corrections down although I did run a 5.91sec 100-200 at one point
Now concerned that if I dump more money into rebuilding the trans and tq converter that ill still be in the same boat come next spring.
yea I've also replaced HPFP, all my meth nozzles are brand new. I've also tried ethanol 
Have you done a compression and leak down test by any chance? I'm wandering if a ring piston landing or something could cause something like this?
Have you done a compression and leak down test by any chance? I'm wandering if a ring piston landing or something could cause something like this?
It sounds like we are all in this boat.
I am pretty sure my plugs are due for a change, so they can come out anyway.
I think seeing 'improvements' on the mentioned changes but, not fix ,might lead me to question if there is a mechancial issue like valve seating/ flow due to carbon build up(leak down can indicate this if there is no smoke from.memory). Therefore needing a wallnut blast or something more. I am going to get the port injectors cleaned as well, though not sure if there is much differences in the afr/fuel trims across banks to indicate this.
I am still a good way from the sort of timing I should be able to get to.
I am pretty sure my plugs are due for a change, so they can come out anyway.
I think seeing 'improvements' on the mentioned changes but, not fix ,might lead me to question if there is a mechancial issue like valve seating/ flow due to carbon build up(leak down can indicate this if there is no smoke from.memory). Therefore needing a wallnut blast or something more. I am going to get the port injectors cleaned as well, though not sure if there is much differences in the afr/fuel trims across banks to indicate this.
I am still a good way from the sort of timing I should be able to get to.
Ok , so run a strong injector cleaner . Then added 93 , to drop down to 18%E . Also got rid of burbles and awitched off linear throttle .
Hmmm... no timing pulls. Good.
However, i have light throttle occasional stumble/missfires.Bad
Eg: cruise control on the highway , very occasional miss etc. So thinking this might be spark plug or coil degredation?
E80/85
Good - light throttle, mid throttle
Bad- timing pulls on full power
E18
Good - full power pulls
Bad - light throttle , closed loop
I might try a light throttle.log today to see what is going on.
Hmmm... no timing pulls. Good.
However, i have light throttle occasional stumble/missfires.Bad
Eg: cruise control on the highway , very occasional miss etc. So thinking this might be spark plug or coil degredation?
E80/85
Good - light throttle, mid throttle
Bad- timing pulls on full power
E18
Good - full power pulls
Bad - light throttle , closed loop
I might try a light throttle.log today to see what is going on.
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Here's a log I pulled today on 94 pump gas+ a small 250cc meth nozzle in charge pipe... some pretty bad correction especially in cyl 4. With ps2's running 20psi on 94 pump alone, logs should be clean & clear of corrections like they used to be for me 2 years ago. setup has not changed. where do I go from here?
Here's a log I pulled today on 94 pump gas+ a small 250cc meth nozzle in charge pipe... some pretty bad correction especially in cyl 4. With ps2's running 20psi on 94 pump alone, logs should be clean & clear of corrections like they used to be for me 2 years ago. setup has not changed. where do I go from here?
Maybe you can also try my process of elimination . You can try the things I did, to look for improvement.
Un check linear throttle and burbles. The later probably does nothing . The former because I recall XHP is designed that way and I wanted to eliminate any TCU/ECU gremlins.
I ran a good PEA fuel cleaner through. I used Nulon brand but, Liquid Molly and other brands have it.
Do a log from 3rd gear or 4th gear not 2nd gear and check if it does the same? My gut tells me that there was allot of wheel spin in 2nd that followed into 3rd causing timing drops. I say this because it looks like the timing tries to clean itself up by the time its mid way through 3rd and into 4th.
Also make sure traction control is completely off when you do the log.
Also make sure traction control is completely off when you do the log.
Ok , so run a strong injector cleaner . Then added 93 , to drop down to 18%E . Also got rid of burbles and awitched off linear throttle .
Hmmm... no timing pulls. Good.
However, i have light throttle occasional stumble/missfires.Bad
Eg: cruise control on the highway , very occasional miss etc. So thinking this might be spark plug or coil degredation?
E80/85
Good - light throttle, mid throttle
Bad- timing pulls on full power
E18
Good - full power pulls
Bad - light throttle , closed loop
I might try a light throttle.log today to see what is going on.
This is interesting. Perhaps I should try some insanely strong injector cleaner and see if it helps my situation. also did you try do more logs after that log? I ask because I often get a very clean log for my first log and then its downhill from there as the car gets oil temps closer and closer to 120c
I never had MHD burble and also don't do the linear throttle response.
The misses you get with cruise control I have gotten those for years on my car and I have never figured it out and I have new plugs and coils. I don't know if its misses per say but the car feels like its speeding up and slowing down its very annoying and the AFR's bounce from 11 to 16 while its doing this. Also it always happens as the car starts coming under load i.e. the road starts to incline. this goes away after a minute or two and it always seems to be triggered by cruise control.
I will do some more logs later but, it wasnt a one trick pony pull, I did another one same day same result.
Once I run through the fuel cleaner ,I might try gradually up the E content and see if its fixed.
Once I run through the fuel cleaner ,I might try gradually up the E content and see if its fixed.
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