Initial fuel pump prime table
03-14-2015, 10:37 PM
#1
TECH Apprentice
Thread Starter
iTrader: (3)
Join Date: Nov 2012
Location: Auburn Alabama
Posts: 339
Likes: 0
Received 0 Likes
on
0 Posts
Initial fuel pump prime table I need to adjust my initial fuel pump prime (if possible) on my 411 PCM, anyone know what table it is located in?? I tune in EFI Live but it should be the same table either way...
03-19-2015, 11:19 AM
#4
Moderator
iTrader: (11)
Join Date: Mar 2002
Location: East Central Florida
Posts: 12,604
Likes: 0
Received 6 Likes
on
6 Posts
In the stock F-body tune I see a couple of things
under Fuel>General, Cranking Fuel section. There is
a Prime "button" which sets fuel pump run time at
10 sec at normal temps. But there is also a Fuel
Pressure Delay that is set to zero, meaning the
"prime" injector pulse can happen before fuel pressure
is built (say, in the case that you have a crappy check
valve, or some other scheme that lets the rails bleed
flat or even vapor-lock).
You ought to see whether you have a problem with
too short a pump pre-run, or if it's really "premature
ejaculation" (prime shot before full pressure). Check
the fuel rail pressure behavior across a cold start
and a hot start, and so on.
under Fuel>General, Cranking Fuel section. There is
a Prime "button" which sets fuel pump run time at
10 sec at normal temps. But there is also a Fuel
Pressure Delay that is set to zero, meaning the
"prime" injector pulse can happen before fuel pressure
is built (say, in the case that you have a crappy check
valve, or some other scheme that lets the rails bleed
flat or even vapor-lock).
You ought to see whether you have a problem with
too short a pump pre-run, or if it's really "premature
ejaculation" (prime shot before full pressure). Check
the fuel rail pressure behavior across a cold start
and a hot start, and so on.
03-24-2015, 09:20 AM
#6
TECH Apprentice
Thread Starter
iTrader: (3)
Join Date: Nov 2012
Location: Auburn Alabama
Posts: 339
Likes: 0
Received 0 Likes
on
0 Posts
My rail pressure isn't always at full pressure is why I was wondering which table to modify. I will look at Table B9104 in EFILive and see what I can do. I believe my pump is only coming on for 3-4 seconds.