Impossible starts, 60-2, cam sync, wasted spark. Help please :)

[chaloux]

Hi guys, new here but I've been using VEMS for a few years with support from Marc Swanson.  Sorry if this is in the wrong part of the forum, feel free to move it. 

My latest build is my Audi 4000 with an AAN out of a Audi UrS car.  I bought a UrS harness and am using the Motronic PNP VEMS.  The car was running when I bought it but needed an engine rebuild.  It was running on 034 IIc, wasted spark, and ran and started great. 

Here's all the important info I believe you need.  I've tried  A LOT of things and am getting somewhat frustrated because when the car starts it runs amazing. 

- 60-2 trigger wheel
- cam sync with stock crank position sensor
- no idle air control valve
- 8.5:1 compression
- fuel pump on all the time while cranking
- I have good spark and the engine was timed with a timing gun

So here's what's going on.  Originally i had the fuel pump off while cranking but it took a very long time to start.  Once it was started it ran great, and would start again the second time much easier.  When WARM the engine starts very easily, after about 3-4 seconds of cranking.

I decided that it wasn't getting enough fuel and I should hook the fuel pump up, but when I did that the engine floods badly.  Okay, not a big deal, I have to change my cranking settings.  So I set my crank VE to 30 and prime pulse 0.  Still seems to flood.  Flooding sucks because it takes a long time to get the engine dry to try again.

I've been reading whatever I could all over the place for insight.  This morning I tried setting cam sync to disable and VOILA, fired up immediately.  Best start I've ever had in the car, instant.  Except it runs like crap.

So I either need to fix my cam sync or I need to set up wasted spark.  I need help either way I go.  I have trigger logs and configs but can't attach anything?

[gunni]

You can create a report in Vemtunes or use

http://www.vems.hu/wiki/index.php?page=FileArea

to upload files.

Sounds like a triggerlog and or regular log would help people assist you.

[chaloux]

Thanks gunni.  I'll get a log right now of the cranking but here is a trigger log and my current config.  I had to re-order my ignition in order to get my cam timing right.  It was 180* out initially.

trigger log
http://mchaloux.com/matt_no_start.triggerlog

comfig
http://mchaloux.com/matt_base_tune_latest.vemscfg

[gunni]

That config has no camsync,

your trigger logs shows what appears to be incorrectly wired VR sensor on the crank input, Can you perhaps do a triggerlog without any plugs in so that the engine speed is as even as possible?

[chaloux]

Hi gunni,

Yes that config had cam sync disabled because I was just messing with things - with cam sync off it'll start immediately but run bad. But all the greyed out settings are what my cam sync settings are.

And when I plug the vr into the crank position sensor connector (stock urs harness, g4 sensor), I get no trigger. I have to connect it to the engine speed sensor connector (g28). Not sure if that is screwing things up or not.

I figured out that a problem I had was flooding. I kept lowering fueling but then tried individual injectors instead of simultaneous. That helped a lot but then I needed to add more fuel. It was going good until this morning when it was colder out, 5 degrees C. It wouldn't start and then I touched the throttle, thinking it was not getting enough fuel, and it flooded.

But I'm wondering if my injectors are not firing at the right time - I had to shift my spark order two steps.

I will get a log with no plugs in tonight. Thanks for the help.

[chaloux]

Here's my latest config

http:mchaloux.com/mbt-ind.vemscfg

[chaloux]

Small update - I enabled hall dirac filtering and it fires up immediately, even better than when cam sync is disabled. It also runs and drives great. It's there any reason I can't run dirac filtering with a 60-2 wheel and vr trigger?