Getting some really odd behavior that is preventing me sorting out the VE table, depending on when I log gives significantly varing results for what look to be the same situations:
log 1, taken on the way to work sat in traffic, engine is ticking over at 1000rpm, ve shows 37%, battery around 12.5-13v and the lambda shows that it running very rich below .65.
https://app.box.com/s/24yn6yqqesl1ot7hkida
log 2, taken on the way home, sat in traffic, engine ticking over at 1000rpm, ve shows 37%, battery around 12.5-13v and the lambda shows .98, pretty much as planned.
https://app.box.com/s/83ez3tnoosi1b04t1sdc
The same has happened on the last few days, it is making tuning impossible. In addition the engine now seems to be cutting out more frequently when in stop/start traffic, this didn't a couple of days ago with what I believe to be the same settings....
Seems it is WBO2 sensing problem. It can not be so rich and read so rich.
In addition you have bad spykes in MAT signal. Sometimes also TPS seems strange - spiky. Wiring?
Gints
Gints
Does the WB02 sensing look like a damaged sensor or that it needs a clean or calibrating?
I have replaced the MAT sensor in the last 200miles, I'll check through the wiring thoroughly, same for the TPS.
As usual, thank you for the help.
Alex
Can I ask why TPS threshold for idle is set at 3?, also, idle is so close to EGO lower threshold, drop that down to 800rpm. That might be the reason why EGO correction is enabled eratically.
VE table jumps from 36 36 in the bottom rows at 1000rpm to 29 55 at 1300rpm. Thats a 20% dropin fueling and 50% hike in almost the exact same spot. this could be another reason why EGO correction is switching on and off, since Lambda reads silly values, it switches off. EGO is leaning out by the pre configured max of 15% yet the lambda is still miles off where it should be.
Another thought. Should the alternator not be putting out more than 12.8v at idle? Saying that, the morning log shows 14v at the same point as the evening log showing 12v. This is another area to consider, the injector voltage compensation. why is there such a voltage swing?
Check all your power and ground connections are good, and have the alternator tested.
Sprocket, thanks for the suggestions:
I've dropped ego correct lower threshold to 800rpm.
What does the TPS value for idle control and what is a sensible value? I have disabled idle ignition control and I don't have a PWM or stepper.
The VE table at 1300 at 0% is lift off/overrun and and 1300 at 1% is accelerating, the figures came from vemstune with a minimum of 200 hits in the cell. edit: just read your stalling issue posts from a few years ago, I'll look to increase the 0% TPS line of the VE table for the 1300 and 1700 rpms to ensure that there is fuel when it gets to idle as mine is also stalling when coming down the rev range.
The alternator is a little race unit that only gives about 45amp, injector compensation value needs sorting, but I want to get consistency with the settings before changing other factors, the 12 and 14v figures have the correct slope as changing the load (lights, fan) at idle reduces the voltage vet the lambda is stable during testing.
I'll be cleaning and checking all power and earths next.
The log view of v3.3_u004869-2013.11.11-08.35.57.vemslog shows MAP=cte=102kPa
v3.3_u004869-2013.11.11-16.33.15.vemslog gives min MAP=102, Max MAP=103 ???
My VT is 1.5.44 (2013.10.18). Something certainly weird somewhere...
fphil, I'm running an alpha-n set-up, the reading you are seeing relates to barometric reading I.e. altitude correction.
of course, stupid I am :)
and even more, since I do not understand why you get 0.65 lambda on the 08.35.57 log.I was thinking that your sensor is not warming well.
Although I was surprised by the high variations of lambda that you get for rather small variations of TPS at 1000rpm on the 16.33.15 log
Before suggesting there is a problem with any hardware, i'd still say the the VE table is miles out and causing massives swings in fueling greater than the 10/15% the EGO can correct. The fact that you have a 'reasonable' fueling at idle is deceptive since as I already pointed out, the values in and around that area are massively rich and lean.
Tune the idle area of the map so that you get lambda 1 and the values in the surounding boxes are of a very similar value and then stretch that across the map to get you somewhere near.
From my experience with Alpha N on ITB's the VE values in and around idle were all pretty much the same, but as the rev's picked up towards the higher end, but at low throttle openings, the VE values dropped off, not rise. Engines can be different, but to have that much of a fueling swing, the VE values, in my opinion show that to be the case.
Other things to consider. The ignition advance at the idle region steps up increasing instability. OK so you want the advance to increase with revs. This is the problem with Alpha N, it's not Speed Density. Manifold depression at low throttle does not necessarily rise much in relation to rpm.
You really could do with another column at 1100 rpm if your idle speed is 1000rpm and loose a column higher up the revs. You could loose the colum below 1000rpm if you don't intend going into that region, or you could keep it, but add more advance at 0 and 1 throttle maybe a value of 25 degrees or so to kick the engine back up to speed if it starts to faulter. Adding the extra column at 1100, you know at idle the values between 1000 and 1100 will all be very similar and not an extrapolated value giving a steady idle. Currently your idle sits on an extrapolation between values in both the ignition and VE tables, and with a 50% hike in fueling from 1000 to 1300rpm on the 1% throttle line. on the 1300rpm column, going from 0% to 1% throttle there is a massive 90% increase in fueling (that is to say 55 is 90% greater than 29)is there any wonder the lambda swings about so much?
Quote from: fphil on November 14, 2013, 07:02:22 PM
and even more, since I do not understand why you get 0.65 lambda on the 08.35.57 log.I was thinking that your sensor is not warming well.
Although I was surprised by the high variations of lambda that you get for rather small variations of TPS at 1000rpm on the 16.33.15 log
It could suggest there is a possible issue with the sensor, but then VE table is all over the show. Any lambda value under a threshold (0.67?) the ECU prevents EGO from working since to have a value that low if there was indeed a problem with the sensor, leaning off might damage the engine.
Having said that, looking at the other log you can see EGO correction max out but lambda values still dive way below target Lambda, EGO cuts out, which I think is a symptom of the erratic VE map.
One thing though, with fueling that rich, you'd smell it, plugs would be BLACK and the exhaust very sooty. If the plugs still show tan/brown, then i'd be inclined to say that the sensor or wiring might be the issue, but the VE table is, in my opinion, suspect.
Stop start traffic is the worst case since you have short sharp runs of acceleration and deceleration in very small time periods. If your VE fueling and Acceleration enrichments are away from ideal you can see an eccess of fuel build up very quickly. I notice Overrun fuel cut is also dissabled.
'Tune the idle area of the map so that you get lambda 1 and the values in the surounding boxes are of a very similar value'
I was also surprised recently to idle in 2 different different idle states, same rpm, same PW, same IACDC but lambda 0.93 in one case and lambda 1.05 in the other. MAT was about 12deg
I do not have much experience in tuning combustion engine, anyway my understanding was that it could be partial combustions which give different lambda values as the volume chamber can be easily expand when there is no torque to exert.
Indeed, as you say, in order to run for sure the same state, one should flatten the VE area around the idle point. This is also necessary, I believe, to get rid of the rpm oscillation at idle.
I have managed to record a log at tick over that appears to show the problems that were identified earlier:
https://app.box.com/s/r414djv8udxxfmpnpa02
(http://locostbuilders.co.uk/upload/Irratic%20running.jpg)
I have changed the connector on the MAT sensor and this appeared to resolve the issue, but looking at the section of the log in the image the current is at it lowest of 11.78 just before the MAT drops around 20 degrees causing additional fueling and lambda to show rich.
I'm about to run a new section of the loom for the MAT sensor as I suspect when the current is higher the fault in the wiring isn't shown, only when the current drops does the resistance drop giving a false temp reading.
Is Vems designed to run with less than 12 volts or do I need to consider a smaller alternator pulley to up its output at lower RMPs?
Another 4mths on and I'm beginning to give up hope, even cycling everyday in the awful British weather has been more appealing than trying to get to the bottom of this issue.
New 60amp alternator fitted, all earths cleaned and new MAT loom fitted.
Ran another set of logs today:
First run of the day and the engine is running really rich https://app.box.com/s/g6o13i0fuo2j90225mhh , after a couple of minutes I turn if off wait 30seconds and restart, the lambda then stays on target (as well as can be expected for untuned) for the rest of the 20min drive https://app.box.com/s/91ir7ztnqst7o4652mi7
Drive home from work and again it stays around target for 20mins, I stop for about 5mins and then record a new log, this time sitting in slow traffic the car has real difficulty ticking over and requires quite a lot of revs to pull away, it then leans out and stalls on a few occasions.
https://app.box.com/s/k8bxc0pebg7vn82nc9bd
Is there anything obvious that I can try?
Disable "Injector staging" by setting unreasonably high threshold values (as suggested by "F1 for help").
I would move all the functions that you drive with low current drivers to the free ignition outputs instead. I simply don't trust them for anything but a small LED.
It might come back to bite you in the ass when you loose the low current driver chip, which then kills power to the trigger input chip (you're running VR sensor) leaving you stranded by the road side.
What size are the throttle blades?
Something is really odd about your fuel map and the lambda sensor, and it can be hard to get a grip without being there.
First look, I would say it's not near tuned yet.
What sucks too is that the TPS signal in itself sucks as a low load signal.
I would probably recommend something more recent than 1.2.6 as well. There were some sketchy things going on, hopefully less so than what we got in 1.2.23.
I am running a second set of injectors, 215cc in the head and 440cc in the TBs. All the low RPM issues that I'm trying to resolve are well before the second set are activated.
So fan and fuel pump are currently on the P259 4 and P259 5, I assume these are the low current drivers you are referring to, I'll move them to an ignition as advised.
Throttle blades are about 40-42mm x 4
I know the tuning is out, but until I can get some repeatable results I don't want to mess with the map any further.
I am questioning my injector deadtimes again:
Option 1 - I have found a set of injector calibration data for the larger set of injectors http://eficomponents.com/specsheets/bluegiant127.pdf
Both sets of injectors are modern Bosch EV6's, the small set are 0280156154 and the larger set 0280156127, I'm curious if Ford have specified very similar/same characteristics. Do the figures in FNPW_OFFSET directly relate to the simplified deadtime table?
Option 2 - moving back to Traditional using the technique Gunni posted; are the values in the help files now correct ie. Injector Opening Time @ 13.2v = 0, effective rampup = 200 (is the rampup figure in the above table?) and rampup voltage compensation = 4080?
Couldn't agree more that something sketchy is going on! I'll upgrade the firmware and see if it changes anything.
As always, thanks for the constructive input, my motivation is slowly coming back.
Hello Se7ensport,
I have reviewed the logs you posted and have some initial observations.
1) start by re-adjusting your accel enrich bins (for an Alpa-N car i suggest: dTPS 15, 30, 60 120 Enrichment 2, 4, 7, 10), your current accel enrichment bins make it engage much to early and with way to much fuel, this might cause the bogging effect you describe.
2) also during accel enrich situations EGO switches off (keeping last correction if enabled, but when disabled like in your configuration) reverting to 100% correction -> result, more fuel.
3) avoid any sharp breaks in the ignition table especially around the driving off area 800-1500 rpm 0-15% throttle (in alpha-N this also leads to sharp VE table steps requirement, because actual airflow into engine is dependant on throttle opening and ignition advance (or rather produced engine torque))
4) avoid enabling the before throttle plate injectors (staging set) on such low airspeed, they work properly only when throttle openings are quite high and airspeed is also high. I recommend minimum rpm 2800-3000 rpm and 40% throttle to enable second set.
5) retune the VE table with ego control off, so measured lambda is close to (a bit richer than) desired lambda.
If you follow all hints above, i am sure you will find the engine behaving more predictable. If any problem persists, please make another datalog (.vemslog) and make a sharing report so i can review (link to this can also be posted on the forum).
Best regards, Dave
Upgraded firmware and vemstune to latest.
Moved output channels to spare ignitions as advised.
accel enrich bins adjusted (dTPS 15, 30, 60 120 Enrichment 2, 4, 7, 10)
EGO freeze correction enabled.
Started it up to make sure it ran and noticed that the spark angle jumped all over the place, between 10 and 14 on tickover. Based on the RPM/TPS table it should be 17 degrees, but ignition based idle control is off, so what is causing the variation?
http://vems.hu/vemstune/sharingcenter/reports.php?cmd=view&key=ID2tEj
Rolled the firmware back to 1.2.6.
using 1.2.23 and at tickover i get 9.5-13.5, using 1.2.6 and i get 19.5!!!!
log using 1.2.6
http://vems.hu/vemstune/sharingcenter/reports.php?cmd=view&key=3PgRoU
log using 1.2.23
http://vems.hu/vemstune/sharingcenter/reports.php?cmd=view&key=Tq1bb3
what is going on?
(looking at your 1.2.23 datalog)
900 rpm is the lowest RPM bin in your ignition table. Below 900 rpm the ignition advance will interpolate between what you got in that table, 15 degrees, and your cranking rpm which is 25 degrees.
You also have to adjust the new table in 1.2.23 which is the CLT/TPS ignition adjust table. You have -32 degrees in that table, better start off with 0.
Please read the notes before using : http://www.vems.hu/wiki/index.php?page=GenBoard%2FUnderDevelopment%2FFirmwareChanges
A default of zero would have been good.
I can't find this table to adjust, which section is it in?... I am using 1.5.24 (2014-01-08) vemstune, downloaded the latest nightly 2014-02-06 but it still opens as 2014-01-08.
It's in the "Tuning" menu like all the other common tables.
I agree, a good default would've been nice.
I'm sure I'm not going mad
scaling is massively out:
http://locostbuilders.co.uk/upload/tmp_DSC_0564-59091739.JPG
(http://locostbuilders.co.uk/upload/tmp_DSC_0564-59091739.JPG)
I'm sure you also "updated the ini files manually" as it is suggested on the firmware changes wiki page?
It's in the Preferences menu.
1.2.23 reads specifically :
as always, VemsTune must be newer than firmware, use the most recent, and don't forget to run iniupdate
Cheers Mattias, "user error" on my part.
Hi Guys,
Safe default values are provided in default_config_1.2.23, but unfortunately due to the way the CLT/MAP Ign adjust table is mapped in memory on firmware upgrade they are not applied default.
I have therefore applied new config criteria (will be fetched through ini update together with the latest ini's) to warn user specifically if if any bad configuration of CLT/MAP Ign adjust table is detected. Of course without the latest ini's VemsTune does not provide warning, thats why we always ask to update ini's first.
Best regards, Dave
Thanks all for the suggestions and for getting the new config running.
I am still getting the same symptoms that caused me to open this thread initially.
I have now captured them in two short log files at tickover, I literally turned the engine off after running for a couple of minutes and restarted it, this caused the lambda to go from 0.65 and off the scale to 0.87.
What is changing within vems for this to happen?
initial start up:
http://vems.hu/vemstune/sharingcenter/reports.php?cmd=view&key=bZjegt
restart:
http://vems.hu/vemstune/sharingcenter/reports.php?cmd=view&key=BC5iQC
James on another thread is reporting similar issues, although no log provided: http://www.vemssupport.com/forum/index.php/topic,2220.0.html
I'm wondering if this might have something to do with the way in which VEMS can run sequential injection without a secondary trigger. A potential problem with that is you will never be sure whether you are injecting on the intake stroke (fuel almost going straight into the cylinder) or the combustion stroke (fuel sitting in the port for nearly half engine cycle), thus a particular engine set up could potentially run differently?......................
the angle at which the injector injects fuel in the port could also potentially cause differences in this sync free sequential system. Are your injectors positioned as the OEM had intended?.... I'm not saying it is a problem, just suggesting other possabilities. I can at least say I experienced a similar but less noticible effect on my engine without cam sync, but it was not so noticable to be concerned about at the time.
Do you have the facility to run a secondary trigger on this engine?
Hi Sprocket
The first stage injectors are OEM and in OEM location.
Fitting a secondary trigger is possible, but a real pain as I need a very specific cam cover that will also hold COP.
I agree with you that the the timing of injection will impact burn efficiency, but this seems to be something else as it is such an extreme difference.
Is there a simple way to rule this out??? would doubling the number of squirts per cycle so that it fires half the fuel on a closed valve and half on an open valve do it, if this is the issue the behaviour should become consistent and irrelevant of cam position in start up.
Hi, just a few questions/ideas.
Does the engine actually feel like it's running that rich? Stupid question I know, but just because a sensor is saying it is, doesn't mean it really is :) At 0.65 you should be seeing black smoke/eyes stinging with fumes etc.
If it is, then the only way it can do that with the same injector pulse (approx. 2.4ms in your log) is if the fuel pressure has gone sky high for some reason or if the secondaries are activating when they shouldn't. Possibly worth disconnecting them entirely for an experiment, and plumbing a pressure gauge in for a bit.
Only other way is a restriction of air aswell. Airfilter being sucked in and wedged and on restart it relaxing and going to a 'normal' state?
I see a lot of faults that are more mechanical than ECU related. We've all been there, scratching your head with a misfire, changing outputs when it's actually an injector failure etc!
Also make sure your ITB's are going back to the same state on idle. Seen a fair few incorrectly assembled and the plates resting at different positions everytime the throttle is blipped.
Just trying to come at it from another angle :)
-Gavin
Great input, I've been right through the ITB's and filter set up even measuring and recording individual vacuum...
When I pull the plugs they are always a tan colour - not as light as I would like, but they are very far from black and dripping in fuel.
Had a massive bit of luck on ebay earlier today and now have a rocker cover on its way for the weekend that is COP and cam position sensor compatible :)
I then found this video: https://www.youtube.com/watch?v=MRNYdMdp-MQ
It is incredible the difference it makes so I'm happy with the outlay and time to get cam sync done correctly, until seeing this I really struggled to believe that it could have such an impact as when I first got my Vems I don't believe cam sync was tunable.
Interestingly enough, the last car I tuned had a very high duration camshaft, and that indeed seemed happiest with the injector angle at around 520. It does make a noticable difference.
Good news with the E-bay find. Hope it puts you in the right direction.
-Gavin
Quotehttps://www.youtube.com/watch?v=MRNYdMdp-MQ
Thanks for the link.
From another point of view, one sees that at 300° injector angle, the afr gets richer and that the idle controller cannot keep the idle stable.
I found this page interesting
http://forums.haltech.com/viewtopic.php?f=16&t=2724
The guys there like to tune the injector angle to have the mixture richer. Although this is not obvious.
I have also quoted:
"More raw fuel out of the exhaust IS NOT necessarily a result of incomplete combustion. After all, it could just be excess fuel that was supplied - all of the oxygen may have been burned. However, it is true that incomplete combustion may result in excess unburnt oxygen and this MAY read lean on the wideband"
Philippe
Since when is oxygen being burned?
In any case. If you have fuel coming out of the combustion chamber that means it´s incomplete combustion, the reasons can be bad atomization, missfire , lack of spark and so on.
It is logical to consider that the richer reading will mean you can lessen your pulsewidth and maintain same effective torque output on the crank but with less fuel, comes in handy during MOT´s and emissions testing.
Alright, but on another hand, if one tunes the injector angle to get the best possible combustion, then the aim is to get less CO and more C02 and leaner lambda.
After then if one wish to have the same previous lambda he/she has to increase the VE value from the map since the Volumetric Efficiency have been improved by the injector angle tuning.
Volumetric efficiency is related to air volume flow only, so most certainly that has not changed. But what can be said is
Lowest possible pulsewidth to give certain target lambda will give the most correct VE representation.
i.e. if you piss some fuel at the wrong injection angle and get lambda 1 and VE of 70, then adjust the injection angle and you then have a VE of 50, 50 is more correct then 70
I was always led to believe that raw fuel in the exhaust (hydrocarbons) is as a result of cam overlap and scavenging, or in worst case a miss fire. The low end hydrocarbons are a result of the mechanical construction of the engine itself for example, trapped fuel between the top ring land and any other quench area in the cylinder which prevents the fuel from burning during normal combustion. Partialy burnt fuel (carbon monoxide) in the exhaust is a result of incomplete combustion (rich mixtures)
Granted at the extreme rich end of the scale you could see raw fuel pass directly through the cylinder as the 'quench' is so great, but in the 'normal' range of combustion, raw fuel in the exhaust, has not been 'combusted' and come from somewhere else other than the combustion stroke.
Always remember that the lambda sensor measures oxygen either as oxygen, or as a reaction of Carbon Monoxide. A rich miss fire results in a lean indication.
a four gas analyzer is your best friend.
Just added cam sync sensor and wired in.
I had assumed that I would need to make the following changes for it to run:
1. within Secondary Tigger, enable camsync and set to rising edge
2. Adjust Injector Angle Curve to suit.
Having done the above and tried injector angles of 200, 300, 400, 500, 600 and 700 (at all rpms) I get a massive back fire at the lower settings and an attempt to start at the higher end but incredibly lumpy. What else do I need to consider as I don't want to risk damaging anything???
10 second log showing running engine and the impact of turning on cam sync:
http://vems.hu/vemstune/sharingcenter/reports.php?cmd=view&key=5y2RkN
Doh! Trigger reference tooth table needed to be updated.
its now running with cam sync.
Initial problem STILL exists.
Summary:
I have made a load of changes to the config, moved to latest vemstune and firmware, spend a fair amount of cash on sensors, wiring, new uprated alternator, moved to fully sequential injection and yet the lambda and running behaviour seems to be a 50/50 gamble.
Initial start runs up to operating temp and it shows massively rich on lambda (if I pull the plugs at this time they are brown, not black and dripping in fuel as I would expect for the lambda figure shown), turn it off and restart immediately and lambda goes straight to target (.97ish).
Initial start:
http://vems.hu/vemstune/sharingcenter/reports.php?cmd=view&key=58lY6t
Restart:
http://vems.hu/vemstune/sharingcenter/reports.php?cmd=view&key=hWzeVk
My suspicion is that it is a VEMS or lambda sensor issue, where can I get these thoroughly tested?
Hello Se7ensport,
The behavior you are seeing matches that of broken lambda sensor, replace LSU sensor (or perhaps you could borrow a lambda sensor from someone for a small test) and i suspect it will be sorted (don't forget todo a free-air calibration before inserting into exhaust).
Best regards, Dave