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

[Bambi]

Hi All

I have a high boost (above 1.5bar) misfire on AAN with LS2 UrS4/S6 Plug and Play Coil Kit. Firmware 1.1.88.I tried upping the charge time to 4.5 ms but no difference to running 3ms. NGK BCPR 7ES Plugs gapped to 0.5mm. Eventually put in 4 Prong 1.8T plugs gapped to 0.5mm and now OK to 1.8bar, but idles with faint hickup and will not do 2 bar boost.

I read the other posts and wonder if I should ether try the parallel 500ohm resistors, but I don't know where to mount them (on the PCB directly it sounds?) or running plugs without the "P" or even without damping resistor? Can the lack of an "R" cause damage or only interference?

Thanx  Leon

[GintsK]

My suggestion is not to use any other plugs than Bosch F5DP0R.
With those 3B engine with native single coil is capable to 2...2.5bar boost.

Additional 500Ohm resistors in parallel with existing 500Ohm are required for 1.8T coils. And just for I259 logical outputs. 1.8T coil has strong pull-down resistor inside. Because of that input current is higher than normally.

From datalog you can found is it exact cylinder what misfires or is it random behaviour. Usually 4 coils are driven by stepper chip (strong signal) and one  - from I259 logical output (not so strong signal).

Gints 

[Bambi]

with those plugs, I have misfire from 1 bar up. Funny enough, with 1.8T coils all is fine (borrowed some) - except that I don't have them, and I bought the LS2 kit as it was advertised as a higher performance option.

In the "normal" setup for the AAN in 1.1.88 is the output voltage to the coils 5V or 12V. The LS2 supplier felt that I had to change the voltage regulator to 14.5V as they want higher charge voltages than other coils. I am starting to doubt wheter these coils can perform as advertised...

If I tried the stepper route as described by Rob, will it help?

[Bambi]

With the motronic 55 plug though, how di I change the wireing and what settings to run for the assignments for 5 cyl AAN?

[Jamo]

if they are EFI LS2 coils they perform very well I use them on a 2.5 stroker ABY

[Bambi]

Yes they are. What plugs are you running and what boost? Whats your driver config and charge time settings?

[mattias]

Depending on coil, wires and plugs and the combination of them you can get into trouble.  Never played with LS2 coils but had issues with noise (USB adapter flipped out, and trigger errors). Simple remedy = resistor spark plugs.
 

[Jamo]

Out of interest why are you using NGK plugs? The stock bosch ones are used as upgrades by the s4 / rs4 bi-turbo owners!

I've had my car to 2 - 2.5 bar boost, quite a few owners on s2forum have used these kits no issues.

[Bambi]

OK, I bought 5 new Bosch F5DPOR plugs - friggen expensive, but worth it I know.. - but now its even worse. I puts the NGK's back and still even worse than before. Now the car wont even drive normally without misfiring all over the place. It's like every time I swap the plugs, it gets worse. I don't get it. The LS2 kit is brand new, the plugs are new, the VEMS is new. Not sure what to do now except drive it till whatever it is fails completely.

Could I have damaged something by running 5ms dwell? Or maybe with a run on non "R" plugs - both of which made no difference.

HELP!  PLEEEESE 

[GintsK]

5ms? Sounds a bit high! Take a look on your datalogs. What is dwell when boost hits?
What is your coil charge MAP scale value???

[Bambi]

I set the charge time to 5ms as a test, but made no difference. I run it at 3.8ms, with mapscale 1. I tried up to 5, still no change. I'm going to borrow my mates 1.8T coils again today. Previously with those I had clean boost up to 2.5 bar with no issues on 2.5ms Maybe the LS2 kit just needs more voltage, but I don't know how to give it to it.

[Ignitec]

I tried 1.8t coils on various vehicles and had never problems with them (from n/a to 2.5 bar). You could drive it with 1.8ms dwell time without misfire up to 2+ bar. I259 outputs with 500 ohm in paralell works just perfect. Maybe you damaged your coilpack with 5ms dwell time.

[[email protected]]

Reading this:
http://ls1tech.com/forums/generation-iii-external-engine/1337141-dwell-time-coils.html
I think you'll be fine with 5ms dwell - all that will happen is that the coils will start to get hot - you may end up overheating the coils, but remember these things are "off" more than they're "on"

[Bambi]

are the I259 outputs marked on the PCB or is there a scematic I must use to identify them?

[GintsK]

Not marked. Here is good pictures:
http://www.vems.hu/wiki/index.php?page=MembersPage%2FGergelyLezsak%2FAssemblyThreePointFive
here is layouts and schematics:
http://www.vems.hu/wiki/index.php?page=GenBoard%2FVerThree%2FSchematic