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No Start - Help please

Posted: Fri Feb 24, 2006 8:55 am
by MurrayA4
I'm using an MSII V3 board.I'm using MT 2.25
I have it wired for Hall input but am trying to get going fuel only so I've added the components for coil negative input per the manual.I'm using this on a 2.5L V6 (Alfa Romeo) and can almost get it running but not quite.It cranks and starts to fire and then dies.I've been working at this for a couple of weeks and need someone's assistance.I've attached a Datalog file which shows what is happening. (for some reason it won't upload.xls so I'll try in a seperate post)

I've set things up as follows:

I have 6 low Z injectors-port
open time 1.5
PWM current limit 30% (I have installed the circuit)
PWM time 1.0
Injector period 66

Req fuel is 15.2 per calc.
2 injections per cycle
Alternating

I haven't touched the ignition settings
My timing is set at 6 deg.BTDC on the distributor.

I enclose also my VE table
and Warmup Wizard screen
and accel wizard

I've followed the manual-changed req.fuel in VE,cold start enrich up and down etc.-No go.
Any help would be greatly appreciated

Posted: Fri Feb 24, 2006 1:41 pm
by Bernard Fife
MurrayA4,

First, go through the tips here: http://www.megasquirt.info/v22manual/mtune.htm#howto

Also, check your timing with a timing light while cranking to be sure it is close.

If those are all good, increase your afterstart enrichment to 45%. let us know what you find.

Lance.

Posted: Thu Mar 02, 2006 12:11 pm
by MurrayA4
Ok Lance I'm back after having to replace my MAP sensor which filled with moisture froze and died :evil:
I went through the troubleshooting steps and tried upping the ASE as high as 45% - no joy.I've confirmed my ignition timing is at 6 deg.BTDC with a timing light.
I've tried changing REQ fuel up and down,tried changing the PW @ -40 (in small increments),the closest she came to starting was when I changed the injector PWM current limit down from 30 - 20% (I have low Z injectors and V3 board with flyback).I've enclosed a segment of my log .As you can see as soon as she goes from cranking to run she dies.Can anyone save my starter motor ?

Posted: Thu Mar 02, 2006 6:47 pm
by MurrayA4
Bump

Posted: Sun Mar 05, 2006 5:48 pm
by MurrayA4
Bump

Posted: Wed Mar 08, 2006 3:08 am
by detcollector
How far down did you go with your req fuel? 11ms pulse width at 500rpm seems way high to me especialy with a VE of 48%. Also stacks up with your 20% PWM being better as that is probably letting the injector only open for 1ms. I should try a req fuel of about 1/3rd your current value just to see if its better. Typical idle pulse width is around 2.5ms. And you proved it fires on a 1.4ms cranking pulse.

Posted: Wed Mar 08, 2006 3:42 am
by MurrayA4
detcollector thanks for the observations.I got it resolved by getting down to the basics :D I pulled my sparkplugs and they were a mess.Fresh plugs, much lower PW @ -40 (6.5ms.)and much lower ASE of 10% and it started with calculated Req.fuel of 15.2 giving a cold idle PW of about 4.2 ms.Onward we go !