MS Help - First start issues

Hey all, I was hoping to get some input from the more experienced megasquirters here. I'm at the point of first start on my (first ms) project, which is isn't, and wanted to see if anything jumped out from my tune, settings or logs since I'm not sure where to go next.

first off, tune and logs (megalog and composites) are downloadable here: https://drive.google.com/open?id=0B3L0pFlfPl3gcVNrYUpxR3ZLWU0

setup basics:

• bmw m52b28 (I6) single vanos into e30 w/ stock injection

• lsx truck coils wired for wasted spark ignition.

• crank sensor is a VR sensor on the 60-2 toothed crank pulley on the front.

• homebrew case and harness for a micrsquirt module running latest firmware

attempting to start, I get chugs and there's at least SOME fuel getting into the cylinders. I've gotten a few pops, but nothing consecutive. It'll do a chug-chug-CHEW-chug-chug-CHEW noise/pattern while turning over continuously.

so yeah, basically looking for help on if it's a tune or settings thing or I should be looking into a parts or wiring issue. really, any insight is welcome.

This might sound dumb and lazy but have you tried starting it with starting fluid? If it fires right up with starting fluid and runs for a few seconds, you need to add more pulse width in your cranking settings plus you confirmed ignition is working correctly. If nothing changes lean it out and see if that makes it better. Still nothing? Check timing and ignition settings and go from there.

Starting is reliant on your initial squirt and the req fuel settings, it doesn't touch the fuel map until it gets over a certain RPM. So focus on those menu areas in TunerStudio.

First thing to check is whether you have decent spark and that you've not fouled the plugs. Next is to verify you have a good, strong battery and starter as you'll be abusing them fairly hard.

In your MS, go to the startup settings and set it to a single start setting and the pulse width to 1.0ms.

Start working from there by tenths until it starts. Set that ms setting into the temp range that best matches ambient temp.

Eventually you'll need to repeat this process for each temp range possible.

These settings will need to be adjusted slightly after the engine cools completely, but only by a few tenths.

OEMs do this over and over again if they don't have a basis to work from. Its annoying and seems to take forever.

Once you get it started reliably, then you'll need to keep it running by adjusting the after start settings and the cells in your fuel map.

If you have a wideband, that can be used manually during startup to adjust the start settings. IIRC you're shooting for around 12:1 during startup before settling into whatever range works best for idle quality.

Get a timing light on it (you'll have to pull the #1 coil out and put a spark plug wire on it to read this) and make sure your timing is correct. If not, adjust Tooth #1 Angle.

Finally got to work on this last night. Did not go well..

I had verified spark for each coil (but not timing). I sprayed some starting fluid into the throttle body to see if it wasn't getting enough fuel and got a back fire out the TB w/ some flames but no apparent damage. Gave it a minute then tried turning it over again to see if any residual fluid left was enough for some life. BANG, valve cover popped, oil cap went flying. Not exactly sure how enough starting fluid vapor got into crank case/head for that to happen but not cause any apparent damage to the intake manifold. sigh

Ouch!

Make sure your ignition timing is correct - not fine-tuned stuff, but are you actually firing the correct coil on the correct stroke? Being 180 degrees off can cause this sort of behavior.

In reply to bluej:

I blew the muffler off my 924 while trying to get it started. That was, um, surprising to say the least :)

Keith Tanner wrote: Ouch! Make sure your ignition timing is correct - not fine-tuned stuff, but are you actually firing the correct coil on the correct stroke? Being 180 degrees off can cause this sort of behavior.

That's what I was thinking. Will be the first thing I check.

at least with the valve cover off it will be easy to find TDC on the compression stroke... Then you should be able to verify exactly where the crank and cam trigger wheels are in relation to their sensors.

Doesn't wasted spark mean the plug fires at BOTH TDC events in the otto cycle? meaning it fires on the between the compression and power stroke, but also fires (the 'wasted' spark) between the exhaust and intake stroke?

Since you say you are using wasted spark, I don't see how you could be 180 (cam) degrees off. I do, however, see how you might be WAY too advanced with your spark (maybe Keith meant 180 crank degrees advanced, meaning the plug fires right at the end of the intake and beginning of the compression stroke). If you light the fire before the intake valves close on the intake stroke, then you will get flames all the way though the intake track. Pressure bypassing the intake valve guides in a similar event would put that pressure into the valve cover area.

I would also check your coil boots. Just want to make sure the spark is actually going through the plug, and not through some other lucky ground between the coil and the block.