Crank Inject All vs Initial Crank Pulse | AEM
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Last seen: 5 years 9 months ago
Joined: 10/18/2014 - 16:49
Crank Inject All vs Initial Crank Pulse

Hi, I am trying to understand the difference between Crank Inject All and Initial Crank Pulse. I have researched and read on multiple forums and it seems like Crank Inject All is much different from the description provided on AEMPro User Guide. Here is the description of both of these below:

Crank Inject All
Units: On/Off
Description: Injects fuel, according to the Initial Crank Pulse table, as soon as the
EMS sees engine speed regardless of cam/crank sensor sychronization.

Initial Crank Pulse table
Units: Microseconds of Fuel vs Coolant Temperature
Description: Injects this amount of fuel at the specified coolant temperature as soon
as the EMS sees engine speed, regardless of cam/crank sensor sychronization.


The only differnece I see is that Initial Crank Pulse has a coolant temperature to scale with. Are these descriptions correct? Can anybody help clarify?


Last seen: 10 min 1 sec ago
Joined: 06/06/2014 - 09:31
The EMS will never fire coils

The EMS will never fire coils or injectors unless Stat Sync is ON.  That's rule #1.  Crank Inject All simply fires all the injectors at the same time when the Initial Crank Pulse fuel is delivered.  Initial Crank Pulse is the first "squirt" of fuel that gets delivered during starting which is then followed by Crank Injector Time.  When Crank Inject All is OFF, the Initial Crank Pulse is delivered sequentially.  

Last seen: 4 years 5 months ago
Joined: 02/20/2016 - 22:10
Hi, I'm trying to help a

Hi, I'm trying to help a friend out who bought a 93 prelude si with a turbo h22a swap and a Series 1 ems pnp.... This car has been passed around for the last 6 years and nobody has had it running!
I have gotten the wiring sorted out and it now has spark, and have the 3+ year old gas out of the fuel system! It cranks, but acts like the timing is way advanced, and the injectors do a "prime pulse"
Then just #4 inj fires while cranking. I have gotten the aem tuner downloaded and communicating with the ecm.
We don't have the funds available to just take it to a "tuner" to get it running...
I'm not a dummy.... I'm an ASE MASTER tech and specialize in diagnostics, but this stand alone ecm is a tad outside of my knowledge base.
This car has had a $t ton of money put into it at some point and it and my friend deserve it to be more than an expensive lawn ornament!
Can someone point me in the right direction?
I've been perusing forums, but not finding a whole lot on the series 1 ems.
I'm not looking for " insider trade secrets" just a starting point to get this thing to start and idle!