High boost misfire on AAN with LS2 UrS4/S6 Plug and Play Coil Kit

[andreNL]

Are the plugs ok when you take them out? If not check injectors wiring and solder mounts especially flyback route.
Check connection IGBT cooling surface that they get cooled correctly.

[Jamo]

Where are you grounding the coils too?

[GintsK]

Are the plugs ok when you take them out? If not check injectors wiring and solder mounts especially flyback route.
Check connection IGBT cooling surface that they get cooled correctly.

IGBTs are built into LS coils. So these coils should be driven by stepper outputs or logical outputs. Means - no IGBT.

[GintsK]

Where are you grounding the coils too?

Good question! There is two grounds for each. right?

[Bambi]

I first had the ground on the tappet cover where the standard coils are grounded, but then moved th ground to the firewall - made no difference. the kit came as plug 'n play so there was only one ground - as per the standards coils.

Maybe I should use the stepper outputs - but I unsure how to setup and rewire for 5 cyl AAN. Is there a guide I could use. I read Rob's post on the subject, but I'm not sure how to do for 5 cyl AAn with the motronic 55 header on it. Has any one done something like that?

[Bambi]

Hi Rob

Do I do all the wiring  changes for the 5 cyl AAN as per your example for the 4 cyl. i.e.

****************************************************

The wires must be swapped from the Ingition pins on the EC36 plug and moved to the EC18 plug as follow
Coil 00 EC36-pin35 to Stepper A EC18-pin4
Coil 01 EC36-pin33 to Stepper B EC18-pin10
Coil 02 EC36-pin34 to Stepper C EC18-pin5
Coil 03 EC36-pin36 to Stepper D EC18-pin11

******************************************************

Must I assign a “Coil 05 EC36-pinxx to Stepper E EC18-pinXX    for the 5th coil.


How does the fact that I have the motronic 55 plug influence things?

For the assignments:

************************************************************

Now we change the ignition outputs Settings->Ignition Outputs from the EC36 pins to their corresponding EC18 pins.
 
So that the coil drivers are mapped to the pins correctly, reflecting the wiring changes made above.
 


Do I just assign in sequence old: i.e.    54231       to     same sequence     EDBCA



Or can the stepper outputs not be used for the 5 cyl AAN?

[Bambi]

I measured the trigger voltage on the coils, and no 3 coil has 5V, rest is 12V. I contacted the supplier of the coils and they said that that is ok as the LS2 coils are driver in the oem application by 5V. They did say however that found that the spark plug connector had been faulty on some of the kits they sold, and that arcing occurs from the HT lead to spark plug connector joint to the head, and from the plug to connector interface to the head.

I noticed that lately under 0.5bar boost I now get firfire of first one cyclinder, and then at 0.7bar a second cylinder misfires as well. They offered exchange the leads for new improved ones, or to give me credit if I return them and buy higher rated magnacore (might have mispelled) leads. Does anyone have recommendations in terms of leads?

[AVP]

That is interesting.

i have had LS2 coils, probably similar to yours for the past year, running dwell quite high, as i was told by EFIexpress that they are ok running 2.5ms charge time and 20 map scale, and have never had any misfires. So if it isnt a spark plug problem, it may be a faulty cable or coil.