VEMS Community Forum

Technical => Ignition => Topic started by: pete95zhn on December 10, 2007, 12:03:35 PM

Title: Ign advance problem
Post by: pete95zhn on December 10, 2007, 12:03:35 PM
Now that I'm solved my req_fuel/PW problem I'm into another one. Actually this was on also before, but now it can be separated into it's own.
The engine idles well with proper A/FR, but when opening the throttle it stalls at 1800 rpm. I intially thought that there's some odd rpm-limiter ( or similar ) on, but now, after looking through last datalog with VEMSLogger Viewer, I noticed one peculiarity. Namely the spark advance does not follow either rpm or MAP, but stays at 19deg, which is the advance for idle rpm/MAP. If it would follow my ign map, it would be 22deg at 1200rpm and 26deg at 1600, but no...just the steady 19deg.
Is there a setting that I haven't noticed that locks the advance?? Or what?
Title: Re: Ign advance problem
Post by: [email protected] on December 10, 2007, 01:26:06 PM
Please can you do an MSQ and Datalog?  Then I can run this up on my test bench and see what the problem is.
Title: Re: Ign advance problem
Post by: pete95zhn on December 10, 2007, 01:57:21 PM
I'll do some loggings more. I can change advance with table editor, but the advance at datalog is 2-3 deg less than in the ignition table. This can also be related to Acceleration Enrichments although I can't get clear indication of that from datalogs.
Title: Re: Ign advance problem
Post by: [email protected] on December 10, 2007, 02:09:15 PM
Acceleration enrichment is fuel only.  There are a number of things that would pull the timing flat:

TPS value for idle threshold (%) is too high then the Ignition based Idle control stuff will pull your
MAT dependent retard will reduce advance if IAT is above

Knock, ALS and Launch control will have a negative effect too.
Title: Re: Ign advance problem
Post by: pete95zhn on December 11, 2007, 07:58:30 PM
Quote from: [email protected] on December 10, 2007, 01:26:06 PM
Please can you do an MSQ and Datalog?  Then I can run this up on my test bench and see what the problem is.

Did you get my mail?
Title: Re: Ign advance problem
Post by: [email protected] on December 11, 2007, 09:00:04 PM
Yes and I've been working away today so I've not had a chance to look.

Rob
Title: Re: Ign advance problem
Post by: pete95zhn on December 12, 2007, 02:17:40 PM
Quote from: [email protected] on December 11, 2007, 09:00:04 PM
Yes and I've been working away today so I've not had a chance to look.

Rob


No problems.

This is just absolutely frustrating...I just spent few hours in the trying to solve this problem by trial and error. Car idles well, like no mods done. Now that I've got A/FR, ignition and idle air adjusted ( IAC bypassed, though... ), the earlier EGT's tendency to creep has almost vanished.
BUT it does not take any throttle. Today's best is 1595 rpm/7% throttle. I can't find anything odd from VEMSlogger. At MegaTune display launch control, antilag and shift-cut are off even when it stalls and reset-counter doesn't increase. Although there is ??misfire?? -sign on. And at VEMSlogger big text about trigger error.
I have played with ignition and VE-maps without any help...
Title: Re: Ign advance problem
Post by: [email protected] on December 12, 2007, 02:45:33 PM
You'll see that I've had a chance to look at this, and I've seen that the minute you get throttle above the idle threshold value that the engine stalls.
I wonder if you are getting any wheel errors?
Its possible that there are triggering issues or that the firmware version that you've come up with has a bug of some variety.
To get this level of R&D support its really a case of putting the tables, configs and datalogs on a wiki page with as much info as you can give - once you have done this let me know and I will wave the wiki page around under the noses of the developers.

Rob
Title: Re: Ign advance problem
Post by: pete95zhn on December 12, 2007, 03:57:54 PM
Quote from: [email protected] on December 12, 2007, 02:45:33 PM
You'll see that I've had a chance to look at this, and I've seen that the minute you get throttle above the idle threshold value that the engine stalls.
I wonder if you are getting any wheel errors?
Its possible that there are triggering issues or that the firmware version that you've come up with has a bug of some variety.
To get this level of R&D support its really a case of putting the tables, configs and datalogs on a wiki page with as much info as you can give - once you have done this let me know and I will wave the wiki page around under the noses of the developers.

Rob

Sorry, it was not my meaning to push...!

Aaalright...so I will put most current data to my Wiki page. Tables and config will not be a problem, but how to put datalogs and trigger logs ( big files ) there...?? Anyway it will not happen before tomorrow, I'm not going to annoy my neighbours any more this evening... ;) ( I have to start it to get trigger log done and my wife says that plates and glasses are shaking in the cupboard when it revs and children are scared of the bang that follows stalling. =) )

BTW, today I managed to get throttle opened over the idle threshold ( 7 vs. 3 deg )

I have been thinking that maybe I should try 12x12 maps instead of 16x14's. Another question is different firmware, am I doomed to this ( maybe highly experimental ) 1.1.24?
I got earlier information from another Finn who inspected my trigger log that when cranking nice and smooth, but the one that's been taken when engine runs has Wheel error flag on it.
Title: Re: Ign advance problem
Post by: [email protected] on December 12, 2007, 09:46:21 PM
You didnt come across as someone who was pushing at all mate :)
A wheel error when running is a serious issue.  With luck we can get the developers interested enough to investigate and get a trigger setup or even code it for your engine.  This will have to be done via the Wiki as they know no other way! ;)

Rob
Title: Re: Ign advance problem
Post by: pete95zhn on December 13, 2007, 11:46:46 AM
I have made an IssueReport, updated my MembersPage ( http://www.vems.hu/wiki/index.php?page=MembersPage%2FPeteKrgr (http://www.vems.hu/wiki/index.php?page=MembersPage%2FPeteKrgr) ) and added ( hopefully all needed ) information. Here's all in zip: http://www.vems.hu/files/MembersPage/PeteKrgr/VEMSpete95zhn.zip  (http://www.vems.hu/files/MembersPage/PeteKrgr/VEMSpete95zhn.zip)

I experimented a little with ignition advances, 8 deg reduced advance allowed 300 rpm more before stalling than basic table.
Title: Re: Ign advance problem
Post by: pete95zhn on December 18, 2007, 04:55:58 PM
Ok gee, I have to say that I'm touched about the enthusiasm and activity with which my IssueReport has been dealt at Wiki...  ::)

I haven't myself done much, except been so desperate that I even checked my grounds. They should be according to installation instructions, power grounds in one bundle of 10mm2 wire to the block and sensor grounds in another bundle of 6mm2 wire to bellhousing. Distance between grunding points is about 5cm, and battery gounds to same point with bigger wire. They all are actually OEM Motronic cables. VR cables are too original shielded Motronic cables, shielding connected to sensor grounds.

What I've also done ( except finding MAF piggyback and unmolested cables for DME ) is thinking about switching boths VR's to one Hall at crank with 60-2 wheel. Would that work without issues. And is my Genboard suitable for that without modifications? While I know that MAF+DME will work like Soviet Union, it is as flexible as Soviet Union too. Anyway I'm not going to garage my car another summer...

BTW, what's Soviet-Russian assbuzzer like? Well, it neither buzz nor fit into your ass...  ;D
Title: Re: Ign advance problem
Post by: [email protected] on December 18, 2007, 06:03:39 PM
I dont know what VEMS setup you have.  If you have a primary VR sensor (I'm guessing that you do) you can run your 4 cylinder perfectly well on a 60-2 with that, and worry about the cam sensor later.

Unfortunately the problem with the current support on the wiki is that they're all working like hounds to get the version 1.1.32 working well, it should sort out all of the 1.1.xx triggering issues, as well as provide switchable maps, a new acceleration enrichment system and a boost table.

And its taking a lot of work to get it all debugged.

Now I know that this doesnt directly help you, but its the only excuse that I can give.

Rob

Title: Re: Ign advance problem
Post by: pete95zhn on December 18, 2007, 06:37:03 PM

Quote from: [email protected] on December 18, 2007, 06:03:39 PMI dont know what VEMS setup you have.  If you have a primary VR sensor (I'm guessing that you do) you can run your 4 cylinder perfectly well on a 60-2 with that, and worry about the cam sensor later.

Specifications:

Board_version=v3.3
Serial_nr= 748

Assembled v3.3 controller

1-wire interface no
ignition driver 4
Knock and EGT yes
LCD and PS2 yes
MAP connection 400kPa onboard (6/4mm pneumatic)
mounting-style screws
PowerFlyback? yes
primary_trigger VR
secondary_trigger Auditrigger

Porsche 944 turbo trigger:

132teeth on flywheel -VR sensor
Crank home (1 pin on flywheel 24.5 tooth, ie 66.8 dec BTDC 24.5 x 2.7272 deg, if i remember right) -VR sensor.
No cam sensor
And no missing teeth anywhere!
Ignition sequence: 1-3-4-2
I.e. trigger is 132+1


Quote from: [email protected] on December 18, 2007, 06:03:39 PMUnfortunately the problem with the current support on the wiki is that they're all working like hounds to get the version 1.1.32 working well, it should sort out all of the 1.1.xx triggering issues, as well as provide switchable maps, a new acceleration enrichment system and a boost table.

And its taking a lot of work to get it all debugged.

Now I know that this doesnt directly help you, but its the only excuse that I can give.

Rob



So there's something to look forward. I hope that 1.1.32 arrives soon. What I'd now need is instructions to check my hardware just to make sure it's bug-free before that new & shiny firmware arrives! The installation will not be just plug'n'play and I don't want to struggle then  with technical problems.
Another thing is opinions from experts about sensibility of switching to 60-2.
Title: Re: Ign advance problem
Post by: [email protected] on December 18, 2007, 10:50:11 PM
If the 60-2 trigger is an OEM design then its an excellent idea.
60-2 is well supported, there are a huge number of installations using it where as the 132+1 is not :(

I know that some of the Audi sensors have the cam VR in the wrong polarity, I wonder if this is the case with this type?
Title: Re: Ign advance problem
Post by: pete95zhn on December 19, 2007, 06:41:46 AM
Quote from: [email protected] on December 18, 2007, 10:50:11 PM
If the 60-2 trigger is an OEM design then its an excellent idea.
60-2 is well supported, there are a huge number of installations using it where as the 132+1 is not :(

It's not OEM, but commercial, and works with MoTec. Picture, although it's not turbo engine, just normally aspirated 944 one: (http://www.clewett.com/products/adapters/944kit.jpg)

Quote from: [email protected] on December 18, 2007, 10:50:11 PMI know that some of the Audi sensors have the cam VR in the wrong polarity, I wonder if this is the case with this type?

Nope, it's been already changed. It didn't even start with that arrangement.
Title: Re: Ign advance problem
Post by: [email protected] on December 19, 2007, 09:01:32 AM
(http://www.clewett.com/products/adapters/944kit.jpg)
That has the right design: A proper "missing" tooth for a 60-2 in that the missing tooth area isnt just a huge gap, but a neutral space.  And a nice solid looking sensor mount.
Title: Re: Ign advance problem
Post by: pete95zhn on December 19, 2007, 10:53:12 AM
Finally some good news!! I got one modified VEX-file from fellow Finn ( Sambas ), and now engine revs beyond 3k. Although there's still some flaws, like slight misfires beyond 2k and MegaTune's rev counter shows values in excess of 16k when engine revs past 3k, it's a start. At last!

I think I'll skip those 60-2 trigersolutions and wait for 1.1.32. Thanks for help!

PS. Rob, do you mid if I send you my trigger logs for evaluation? I'll take them most likely only after Christmas.
Title: Re: Ign advance problem
Post by: [email protected] on December 19, 2007, 11:34:38 AM
If Sambas is on the case then you have a good friend there, he's the bloke who seems to be doing most of the major development work - he's the one doing the new acceleration enrichment and boost PW maps.
Title: Re: Ign advance problem
Post by: pete95zhn on January 18, 2008, 07:17:13 PM
I finally got myself an oscilloscope ( laptop attached ) and it solved almost all my problems ( concerning the car, I mean... ;) ). I had, according to instruction I got in July, changed the polarity of reference ( secondary VR ) sensor. That was not good idea, because the trigger signal was inverted. I switched the wires back to original and the engine works smooth as silk. No trigger flags or misfires, EGT dropped abour 100C and MAP at idle is around 39 kPa...

I feel good.
Title: Re: Ign advance problem
Post by: [email protected] on January 18, 2008, 09:15:59 PM
Excellent news!  I think the VR polarity swap was soley for the Audi engines.
Normally 'scopes are not needed (although very handy) for known setups, but that trigger on the 944 had not been tried to my knowledge.

I hope you have fun tuning it for the summer season.

Rob