High boost misfire VEMS and LS coils

[V6quattro]

I have some problems with my car at the moment. I made a complete new loom for my VEMS. Engine runs nice like before only now i have misfires at high boost. Running around 1bar all is perfect but at 2,2bar i have problems. Running LS coils i got from EFIExpresses 3 years ago and new BKR8E-11 plugs gaped at .5mm or .020" . As far as i know all the coil wiring i did is good. If i remember right i used 1.5mm2 wires and a 20A fuse.


I made some log's and i noticed when looking at the individual-power the misfire occurs on cylinder 4 right?

Can someone pleas look at my log and see if there is something not right and i don't see?

http://www.mijnbestand.nl/Bestand-VC3CO3FE3NAE.vemslog

http://www.mijnbestand.nl/Bestand-C8AMBFZMKZRH.vemslog


Tanks!

[a4kquattro]

I have some problems with my car at the moment. I made a complete new loom for my VEMS. Engine runs nice like before only now i have misfires at high boost. Running around 1bar all is perfect but at 2,2bar i have problems. Running LS coils i got from EFIExpresses 3 years ago and new BKR8E-11 plugs gaped at .5mm or .020" . As far as i know all the coil wiring i did is good. If i remember right i used 1.5mm2 wires and a 20A fuse.


I made some log's and i noticed when looking at the individual-power the misfire occurs on cylinder 4 right?

Can someone pleas look at my log and see if there is something not right and i don't see?

http://www.mijnbestand.nl/Bestand-VC3CO3FE3NAE.vemslog

http://www.mijnbestand.nl/Bestand-C8AMBFZMKZRH.vemslog


Tanks!

use a coil tester like this:



to isolate any possible weak coils or weak spark plug wires.

[popdemonic]

try to regap the tips a bit closer.

[GazzaG60]

More charge to the coil

[V6quattro]

use a coil tester like this:



to isolate any possible weak coils or weak spark plug wires.

Hy Marc thanks for your tip. I actually forgot i have one of those at work .
I will do some test's tomorrow and let you know.

try to regap the tips a bit closer.

Last year my car run perfect on a 0.6mm gap. Now i have set them at 0.5mm but still misfire. I don't think i should just regap them closer and drive it that way. I think there is something wrong.

More charge to the coil

Last year my car was perfect on this map so i only like to do this when all the coils/wires and plugs appear to by fine.

But by saying more charge to the coil you mean upping the time in Vemstune => Basetune => ignitionsettings => Ignition dwell settings => Coil charge time @ 13.2V ???
Its now set on 1.98ms whats the max i would use?

Tanks!

[jade]

Hy Marc thanks for your tip. I actually forgot i have one of those at work .
I will do some test's tomorrow and let you know.


Last year my car run perfect on a 0.6mm gap. Now i have set them at 0.5mm but still misfire. I don't think i should just regap them closer and drive it that way. I think there is something wrong.


Last year my car was perfect on this map so i only like to do this when all the coils/wires and plugs appear to by fine.

But by saying more charge to the coil you mean upping the time in Vemstune => Basetune => ignitionsettings => Ignition dwell settings => Coil charge time @ 13.2V ???
Its now set on 1.98ms whats the max i would use?

Tanks!

on LS 2 coils you set the dwell to 5

[V6quattro]

on LS 2 coils you set the dwell to 5

Hello Jade. So you mean setting Coil charge time at 5ms?

Another question: As you car see in the photo the Coil charge time map scale is high. Does that mean the charge time rises when on boost or am i wrong?

[jade]

Hello Jade. So you mean setting Coil charge time at 5ms?

Another question: As you car see in the photo the Coil charge time map scale is high. Does that mean the charge time rises when on boost or am i wrong?

Not a Vems expert But here some info

http://www.jfetech.nl/epages/080402....ducts/LS2-Coil

[Erikk]

I run BCPR7ES @ 0,5mm gap with no problems at all.

[jade]

Looks wrong to me, But As Stated No Expert

This looks good to me

Dwell 5 ms

Duration 2 ms

[Mcstiff]

F1 is your friend:

Coil Charge Time MAP Scale
Dwell is extended by (MAP - 70kPa) * Coil Charge Time MAP Scale/4096, but no more than +0.4 (40% extension that is *1.4).
Examples:

0 : no dwell extension at all (neither voltage nor MAP based): Coil Charge Time @13.2 is used. Mainly used to set at fixed pulsewidth for external ignition amplifiers (CDI or smart coils).

1 : The recommended value, only voltage based dwell extension (max *2, when voltage is at or lower than 7 Volts).

2 : 40% reached at 890 kPa, and 1.5% at 100 kPa.

3 : 40% reached at 616 kPa, and 2.2% at 100 kPa.

5 : 40% reached at 400 kPa, and 3.6% at 100 kPa.

10 : max dwell-extension +40% reached at 234 kPa because (234 kPa - 70 kPa) * 10 /4096 = 0.4. This is a lot of extra charge time! Take care if using a higher setting than this.

20 : max dwell-extension +40% reached at 152 kPa because (152 kPa - 70 kPa) * 20 /4096 = 0.4

values 2..255 : Battery voltage based extension is automatic. Slope of MAP-based dwell-extension is configured with this variable. MAP-based extension is max *1.4 (+40%), while total scaleup (vbattmultiplier * mapmultiplier) is max *2.

Do not use values higher than 20, as this is likely to overheat/destroy your coils.
Higher value means higher slope (so max dwell extension reached earlier). Take care not to overload the ignition output or the coil (use lower Coil Charge Time @13.2V so you only get extended dwell when really necessary).

[A80Avant]

I have that set at 20 at Marc's suggestion for the LS2 coils.

[popdemonic]

since you drive a car and normally the tips could start to corrode that's why you
might need to regap them again especially running under high boost.i found the
copper plugs is prone to be faster corroded than iridium's.my NGK's Iridium started
to misfire under 23psi after 10,000kms.i decided to regap them down to 0.4mm iirc.
you might try to incerease your coils charge time since it's much easier than pulling
those spark plugs off but be careful on toasting your coils if you increase too much charge time.

[V6quattro]

since you drive a car and normally the tips could start to corrode that's why you
might need to regap them again especially running under high boost.i found the
copper plugs is prone to be faster corroded than iridium's.my NGK's Iridium started
to misfire under 23psi after 10,000kms.i decided to regap them down to 0.4mm iirc.
you might try to incerease your coils charge time since it's much easier than pulling
those spark plugs off but be careful on toasting your coils if you increase too much charge time.

First thing i did was putting new plugs in gaped at 0.5mm and sadly that didn't help. I did increase the charge time today and the car runs perfect now. I only don't like the fact that the car was fine for 5000km and now i have to adjust the charge time a lot to let it run right.

[V6quattro]

So as you can read i played with the car today.

I made a movie off the coil test en noticed the coil for cylinder one is weak. Its really noticeable when i set the charge time and dwell at 1. Coil 1 is weaker than all the others as you can see in the movie. At my original settings and when i set the dwell at 5ms its less noticeable but still not good.

I have put the charge time at 1 and the dwell at 5 and now the cars runs nice on high boost. But to be sure i will order 5 new coils at jfetech.nl