Author Topic: engine stalls after start  (Read 20247 times)

Offline rob@vems.co.uk

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Re: engine stalls after start
« Reply #15 on: February 15, 2008, 02:39:48 pm »
Are you still getting spark?  If so pour a little fuel down your throttle body and crank the engine, you should be able to get the engine to fire and run briefly.

What was the problem with the crank signal?

Offline Timmo6

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Re: engine stalls after start
« Reply #16 on: February 15, 2008, 02:54:20 pm »
The trick with the TB is kind of difficult because my TB is pointing downwards

the cranksignal was poor because the trigger(2 bolts 180° apart on the crankpulley) were either too far from the sensor either too close(touching). Now its not perfect yet but I have atleast a clean cranksignal.
Have to see if I have spark and if my injectors are firing the way it should. Can I just hook 4 small 12v 5W lights on the injectorconnectors and see if they blink?
I will test the spark with a timinglight.
I can try this tommorow.

Offline rob@vems.co.uk

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Re: engine stalls after start
« Reply #17 on: February 15, 2008, 06:49:37 pm »
I think its clear from the PW graph that the injector pulse width drops to zero once the afterstart enrichment has finished.

Offline Timmo6

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Re: engine stalls after start
« Reply #18 on: February 16, 2008, 08:17:49 am »
and what can be the reason? is it something software or hardware?
this is my latest msq file http://www.box.net/shared/2141ipoo4g
and datalog http://www.box.net/shared/4uro5obk0c

« Last Edit: February 16, 2008, 08:38:51 am by Timmo6 »

Offline rob@vems.co.uk

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Re: engine stalls after start
« Reply #19 on: February 16, 2008, 09:56:41 am »
That datalog shows spikes of 25500rpm.

Your VE table is as low as 10 down in the bottom left hand corner - that should all be around 50 shouldnt it?
Also your lambda table looks completely wrong, theres no way that you want to achive a target lambda of 1.11 at the lower end.

The fuel PW is calculated then divided by the lambda setting - so as a rule of thumb (ignore air temp compensation for this):
(7.2ms @ 55%ve)/1.11 = 3.96/1.11 = 3.56ms

Just for a bit of an experiment, in Settings->Priming Cranking Afterstart set the cranking threshold to 3000 rpm, this will keep the ECU in the cranking phase and the engine should achive a fairly acceptable idle on this alone.

Once this is achived bring down the cranking threshold and you should see the point where the changes from cranking to the after start enrichment phase, if you're in the fuel tuning screen you'll see where the fueling is going wrong on the table by watching the location and the PW guage drop.

Offline GintsK

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Re: engine stalls after start
« Reply #20 on: February 16, 2008, 12:44:50 pm »
I see problem due to added TVS diode.

You may need much much longer PW for injectors as previous.

 In datalog picture lowest value is not 0, Rob. There is 2.9ms. Witch can be about 3x less than needed.

Offline rob@vems.co.uk

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Re: engine stalls after start
« Reply #21 on: February 16, 2008, 12:51:50 pm »
I see problem due to added TVS diode.

You may need much much longer PW for injectors as previous.

Good point, it should be possible to increase the PW by just increasing the required fuel value.

In datalog picture lowest value is not 0, Rob. There is 2.9ms. Witch can be about 3x less than needed.

Its difficult to read without the cursor - eitherway theres not enough fuel - TBH I was looking for some kind of fuel cut.

Offline Timmo6

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Re: engine stalls after start
« Reply #22 on: February 16, 2008, 12:57:11 pm »
OK thanks will try that
but I still have problems with my trigger
I have a triggerwheel with 2 teeth 180° apart.
Its two 8mm bolts (the thread of it).
If I put them too close to the sensor it hits and misfires,if I put it a very very very bit furhter away it doesn't read (triggererrors) the trigger anymore >:(
I tried to put the bolts on the thread in order to have a bigger triggersurface but then there is absolutely no trigger anymore?????
Can someone check my trigger parameters please?
Primary trigger =3
Edge= Rising
Type=coiltype
the rest is disabled
TDC after trigger=61
Number of teeth on wheel=2
Crank min period=1200
Angular width of tooth=0
Tooth relation normal=118
Tooth relation missing=181
Angular width of missing tooth=0
Engine phase when to reset=255

Thanks

Offline rob@vems.co.uk

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Re: engine stalls after start
« Reply #23 on: February 16, 2008, 03:51:21 pm »
Which pin are you powering your Hall sensor from?

Are your p259 channels still working?

I'm wondering about the possability of your 5v feed not being up to spec and the net result being your Hall sensor's lack of sensitivity

Offline Timmo6

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Re: engine stalls after start
« Reply #24 on: February 16, 2008, 08:04:46 pm »
I have pin28 as a +5v for the Hallsensor and pin29 as a +5v for the TPS.
The TPS is working as it should but I will check the +5v of the Hallsensor.

Offline Timmo6

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Re: engine stalls after start
« Reply #25 on: February 17, 2008, 04:36:59 pm »
PROBLEM SOLVED!
I had a few issues to solve:
1. the hall sensor doesn't like a stainless steel bolt on the trigger
2. With 30v TS diode no PWM is allowed so 100% is needed
3. I had a coil wiring issue with the 12v supply due to disconnected stock wiring of the coil

so for now nice idle without trigger-errors

Thanks guys for the quick help! Its nice to have some knowledgeable people around.
 ;)Tim

Offline rob@vems.co.uk

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Re: engine stalls after start
« Reply #26 on: February 17, 2008, 05:01:35 pm »
No problem ;D

Now lets see your installation up in the projects section, with some pictures!

Rob