Crank to run taper (s)

[B1ack_Mi16]

Is it possible to set the crank to run taper as a function of time instead of just as a constant?

My problem is especially when engine has heat soaked after stopping a hot engine, it seem to need a lot of extra air from the stepper motor to be able to start.
But once it really starts the rpm rises quickly to 3000rpm and then fades down linearly during the 7 seconds I've set as crank to run taper...

However it is a bit silly revving 3000rpms during start, so I suppose the valve ideally should've closed quite a bit just after starting, and then tapered further down the last steps.
Is it possible to get this tweaked in somehow, or should I rather start looking in another direction to correct the problem? I guess the intercooler and everything is quite heat-soaked when this happens.

[motthomas]

Are you sure you are not just having to cover for the fact that you have too much ASE?

Sent from my GT-I9305 using Tapatalk

[64bit]

Crank to start taper shouldn't be an issue if your idle cranking duty steps, and idle warm-up/idle initial tables are set right.

Sent from my SAMSUNG-SM-G930A using Tapatalk

[micotito]

Are you sure you are not just having to cover for the fact that you have too much ASE?

Sent from my GT-I9305 using Tapatalk

How can ASE reduce RPM? ASE will change AFR but no RPM, 3000 RPM can be rich and also lean.

[motthomas]

Im referring to the way you say you need a lot of air to start the engine which then seems too much when you get going.

It could be that you are putting too much fuel in either during cranking or directly after it runs meaning you need to open the stepper motor more than ideal just to get the engine to fire. Then once you clear the excess fuel it runs like the throttle is cracked open too much causing the high revs.

Sent from my GT-I9305 using Tapatalk

[B1ack_Mi16]

Could be... I've got testing numberplates for 22 July so just 30 mins left and I'm off to do some actual driving after more than 8years of building!

[B1ack_Mi16]

Could it be a problem that it cranks with "Wasted COP" or injects on every cycle?

It's running fully sequential but if it cranks injecting twice instead of once, might there be far too much fuel hence the need for so much air?
Or is the fuel amount just 50% in each of the cycles compared to if one only injects once?

[motthomas]

Potentially. I don't know your setup. As a quick test you could just reduce your cranking PW or ASE particularly at higher temps where you typically see issues and see if you can get the engine to start easier.

Sent from my GT-I9305 using Tapatalk

[billr]