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long crank slow start

 
Old 07-21-2018, 09:28 PM
  #1  
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Default long crank slow start

hello to those kind and wise enough to know what's going on and help.

so basically i got a new pnp2 went to start it and it took about a minute of cranking and power cycles to get the car to start. I figured it was the old "you never start a new computer on the first try" thing. then i tried to start it again and same thing. i was able to play with my timing and fuel, and now the car starts after ~ 10s! I dont think that is good enough so I'm here for advice. I know my way around tuner studio but I am NOT a tuner.
What I have done so far:
checked base timing and set to 10 deg.
set timing map to this:

set fuel to this:


all help is appreciated!
anything else needed available on demand!
Attached Thumbnails long crank slow start-troubled-timing.png  
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Old 07-21-2018, 10:15 PM
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So i'm no expert, heck i'm barely a novice so I may be wrong. These are the notes I have regarding start-ups that I wrote. I'm hoping somebody more experience can chime in and confirm if what I wrote is correct. If so, the notes may be of help to you. If they are incorrect somewhere, then please tell me

Fuel Prime (Pulse Prime Table)

Fuel delivered with key-on. This shoots fuel into the walls and back of the valve to remove air from system. This helps when starting engine when cold starting.

Cranking Fuel Table

After Fuel Prime, the Cranking Fuel Table takes effect. Cold engine needs more fuel than a warm engine. This is coolant temperature based

Lot of cranking means more fuel needed.

Hard cranking that requires throttle needs less fuel

After start Enrichment (ASE)

Occurs right after Cranking Fuel Table for when the car starts to idle. As the engine warms up (20 or so seconds), the number tapers downwards as less fuel is needed. The main Fuel Table is used after ASE ends.
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Old 07-22-2018, 07:42 AM
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Originally Posted by skylinecalvin View Post
So i'm no expert, heck i'm barely a novice so I may be wrong. These are the notes I have regarding start-ups that I wrote. I'm hoping somebody more experience can chime in and confirm if what I wrote is correct. If so, the notes may be of help to you. If they are incorrect somewhere, then please tell me

Fuel Prime (Pulse Prime Table)

Fuel delivered with key-on. This shoots fuel into the walls and back of the valve to remove air from system. This helps when starting engine when cold starting.

Cranking Fuel Table

After Fuel Prime, the Cranking Fuel Table takes effect. Cold engine needs more fuel than a warm engine. This is coolant temperature based

Lot of cranking means more fuel needed.

Hard cranking that requires throttle needs less fuel

After start Enrichment (ASE)

Occurs right after Cranking Fuel Table for when the car starts to idle. As the engine warms up (20 or so seconds), the number tapers downwards as less fuel is needed. The main Fuel Table is used after ASE ends.
That actually helps a lot! i will look through those tables and see whats going on! any clue as to where values should be?
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Old 07-22-2018, 07:47 AM
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It's all dependent on the car. I am struggling with this as well. It is trial and error. Once you get the car idling playing with the idle ve table will help stabilize it. Ensure you have no vacuum or boost leaks or you wont ever get a stabile idle. Make sure base timing and all sensors are calibrated right. Playing with priming pulse helped me a lot.
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Old 07-22-2018, 12:05 PM
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Remember you'll generally be cranking below 500rpm, and at 100kpa, so everything is based off the 500rpm/100kpa cell. So in your case your ve is 58, timing is 18 degrees.

You can try two things, bump that fuel cell up ~10-20% to see if it needs more fuel, or crack your throttle while cranking to see if it wants more air. If that's the case, you'll want to increase your cranking duty.
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Old 07-23-2018, 11:36 AM
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Originally Posted by curly View Post
Remember you'll generally be cranking below 500rpm, and at 100kpa, so everything is based off the 500rpm/100kpa cell. So in your case your ve is 58, timing is 18 degrees.

You can try two things, bump that fuel cell up ~10-20% to see if it needs more fuel, or crack your throttle while cranking to see if it wants more air. If that's the case, you'll want to increase your cranking duty.
So i adjusted the cranking duty and it starts fairly quickly now! the only thing is i noticed sync flashing on and off rather being steady while cranking. Is this normal?
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