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Unreliable engine starting?

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Old 01-17-2010, 03:47 PM
  #81  
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Originally Posted by CRAIGO
Well I've had a play with my settings and things have improved a little. Sadly I don't think we'll see temps as low as they were a few ago (-6degC and lower) so I'll never really know for sure about my cranking PWs at that temp range.

One thing that has really helped alot for me is reducing the cranking advance back to 12deg, set my ASE fixed map for 3 seconds at 84kpa and also make sure that my spark map at 84kpa is also set to 12deg at idle regions and raise the cranking RPM to 450. This means that during cranking my timing is always fixed at 12deg, even when the engine catches slightly and triggers ASE my fixed map value ensures that spark is still firing at 12deg and will do for 3 seconds after the engine has caught.

I've not heard any kicking back sounds yet and cranking for me at 12deg is loads faster too.


I basically did the same but I had not thought of setting the spark map
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Old 01-19-2010, 03:48 PM
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Do we want to continue this thread moving on to how the motor runs after start up????

I'm pretty happy with how mine starts and now I'm trying some settings given to me by DIY hopefully colder weather will not affect things by much...

The main items that I am trying to address R idle fluctuations, idle sag between shifts.

I changed the following as per reccomendations from DIY via email.

Min dc from 21 to 22 ( to help with idle droop )

Fast idle "lower" 130 to 130

Slow idle ( upper) 169 changed to 140 RPM

Slow (warm) idle raised to 1000

VTPS theshold ADC from 150 to 10

Idle Activation 500 changed to 250

Dashpot settle time from 47 to 80

Dead band range 130 changed to 50

Fast recovery RPM 15 changed to 5

Slow recovery RPM 100 changed to 75


I would like to hear if anyone else fudged around with the above issues and settings and what they did

Last edited by poobs; 01-20-2010 at 03:05 PM.
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Old 01-21-2010, 06:06 AM
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I think I've got the "kick back" starting nailed now. I'm giving it 2 more days before I cheer (4 more cold starts, morning and night). With my car It's all in the cranking timing/cranking rpm and most importantly, the spark angle at your fixed ASE map value.
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Old 01-21-2010, 08:35 AM
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Good luck !!!
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Old 01-21-2010, 11:18 PM
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Well im glad im not alone, I get the hydrolock too. Only in the winter though. Scares the **** out of me every time it happens, makes me think the rods are gonna bend and the engine is gonna start to clank after it starts. Reducing PW's at crank for the colder temps helps alleviate it from happening often but it still requires 2 cranks to get going.
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Old 01-22-2010, 12:01 AM
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Originally Posted by poobs
Do we want to continue this thread moving on to how the motor runs after start up????

I'm pretty happy with how mine starts and now I'm trying some settings given to me by DIY hopefully colder weather will not affect things by much...

The main items that I am trying to address R idle fluctuations, idle sag between shifts.
What do you mean here...?
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Old 02-15-2010, 09:02 PM
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It has been rather cold here and despite all the things I tried I am ( as far as I can tell) back to all the base tune settings for idle, cold crancking etc.

The motor stalls at least twice and does that hard crank thing too.

Once it warms up it runs nice but the idle wanders and this reallt makes for not too smooth shifting. I increased the fuel cut off delay and this seemed to help a bit.

I'm also wondering if changing settings so that PWM is used only during warm up will be better. I'll just let the idle rely on the A/F table ( ? )
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Old 11-19-2010, 05:54 PM
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This thread was greatly helpful. My car has over 10.5:1 comp and I had the hard start problem so bad I thought i needed a battery. Put the cranking rpm up to 400 and timing at 8 degrees(it was at 12). Starts up pretty damn good now. Search feature is my friend.
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Old 11-19-2010, 09:14 PM
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Originally Posted by 1cockyz
This thread was greatly helpful. My car has over 10.5:1 comp and I had the hard start problem so bad I thought i needed a battery. Put the cranking rpm up to 400 and timing at 8 degrees(it was at 12). Starts up pretty damn good now. Search feature is my friend.
Good!

Boy this thread brings back memories
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Old 11-20-2010, 04:17 AM
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Yeah me too!

Funnily enough since installing a standalone MS2, I have had not a single engine kick-back/starter stall event. That noise is gone for good. I seriously thought I'd be paying out for a new starter or flywheel if it carried on with my MS1 in parallel.
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Old 11-20-2010, 09:44 AM
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Originally Posted by CRAIGO
Yeah me too!

Funnily enough since installing a standalone MS2, I have had not a single engine kick-back/starter stall event. That noise is gone for good. I seriously thought I'd be paying out for a new starter or flywheel if it carried on with my MS1 in parallel.

So a properly tuned MS2 does away with all that starting weirdness ?
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Old 11-20-2010, 01:58 PM
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A properly tuned MS1 starts like OEM.

Poobs changing the CPU isn't a magic wand, you still need it tuned correctly.

It took me a long while but I eventually got my MS1 to start like OEM, learning to do it yourself is hard, but it's be hard whatever ECU you have.

Craigo is - -dunno if lucky is the right word - but the base tune that comes with this E-DIYPNP is provided by someone who knows how to tune and is tailored to a degree to the users car, that makes a big difference over the MSPNP
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Old 11-20-2010, 02:12 PM
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Originally Posted by richyvrlimited
A properly tuned MS1 starts like OEM.

Poobs changing the CPU isn't a magic wand, you still need it tuned correctly.

It took me a long while but I eventually got my MS1 to start like OEM, learning to do it yourself is hard, but it's be hard whatever ECU you have.

Craigo is - -dunno if lucky is the right word - but the base tune that comes with this E-DIYPNP is provided by someone who knows how to tune and is tailored to a degree to the users car, that makes a big difference over the MSPNP
You must be related to my wife and her family - putting words in my mouth


So a properly tuned MS2 does away with all that starting weirdness ?
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Old 11-20-2010, 04:23 PM
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its all in the tune.

timing, idle valve position, warmup enrichments, cranking pulsewitdh, o2, etc. all come into play.

with that said, you should have no problems getting it to start, idle and run better than stock, you just need to invest time. ms-i, ms-ii, or ms-iii.

I can start the car in 20*F weather or 110*F weather all the same.
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Old 11-20-2010, 05:04 PM
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Cool!

Right now I'm trying to bling up my Greddy manifold and DP before installing it. Just some de rusting and barbeque paint.

I'll tap you gus for profound knowledge when I'm ready to tune for boost, tip-in,AE and cold cranking stuff.

Last edited by poobs; 11-21-2010 at 09:02 AM.
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