Cranking PW question

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JAM
MegaSquirt Newbie
Posts: 29
Joined: Sun Jan 22, 2006 6:58 pm
Location: Cincinnati,OH

Cranking PW question

Post by JAM »

I need some clarification on the cranking pulse width. What parameters effect the pulse width while you are in cranking mode?

I have my cranking RPM set, and that shows up correct in the MLV ( it shows in cranking mode up to the correct rpm point).

As far as the pulse width, I have my cranking PW for low temp and hi temp set to the same while I was figuring out where it liked to fire for the given temp, but that does not match the PW that I am seeing in the datalog at cranking, it is higher. I searched and I could not find a full explanation of everything that effects the PW during cranking. The car already runs etc. so this is not a problem, I was just want to understand if somebody can enlighten me or point me to the info. My thought is that the voltage correction factor adjusts the PW at cranking since the voltage drops down and gives it a longer pulse?
"Any problem that is persuasive, persistent, or unprecedented is unlikely to be solved by hand me down principals."
grippo
Site Admin
Posts: 286
Joined: Mon Feb 16, 2004 6:55 pm

Re: Cranking PW question

Post by grippo »

Cranking PW has corrections for baro, air temp, and battery voltage. The injector open time is also added to it.
JAM
MegaSquirt Newbie
Posts: 29
Joined: Sun Jan 22, 2006 6:58 pm
Location: Cincinnati,OH

Re: Cranking PW question

Post by JAM »

Thanks for the reply, I have looked closer and the output number makes more sense.
"Any problem that is persuasive, persistent, or unprecedented is unlikely to be solved by hand me down principals."
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