holley hp efi stumble
12-06-2014, 09:46 PM
#1
holley hp efi stumble Hello i am having trouble with a stumble when i first press throttle? Running holley hp efi. Car dies when put in gear also. Im hoping these 2 things are connected. Any ideas? i have moved the AE VS TPS TO 7 and ae vs map to 5. I have move these all around no difference. Thanks
12-09-2014, 08:08 PM
#2
You gotta get the base fuel map correct first...
Sounds like a lean spot or a rich spot...
When you press the throttle, as tps roc changes... if it sees more than 10% of the base fuel table value, it switches off learning and closed loop briefly and treats it as a transient..
So you may have to move slowly in the area where its happening...and maybe even manually change values to clean up the fueling...
You cannot rely on just the ecu to get fueling 100% correct..
Then, after base fuel table is correct, you can do a data log and make adjustments to the TPS And MAP Roc tables based on what you see in the logs. These are the tables that will fix throttle change stumbles.
Sounds like a lean spot or a rich spot...
When you press the throttle, as tps roc changes... if it sees more than 10% of the base fuel table value, it switches off learning and closed loop briefly and treats it as a transient..
So you may have to move slowly in the area where its happening...and maybe even manually change values to clean up the fueling...
You cannot rely on just the ecu to get fueling 100% correct..
Then, after base fuel table is correct, you can do a data log and make adjustments to the TPS And MAP Roc tables based on what you see in the logs. These are the tables that will fix throttle change stumbles.
12-09-2014, 08:11 PM
#3
Also..
I very rarely have to make changes to these tables if you don't have too drastic of a setup...
On a Basic heads and cam combo in a daily driver...the preset tables in the Ls1 global setup usually works great..
But only if you get the base fuel table correct to begin with.
I very rarely have to make changes to these tables if you don't have too drastic of a setup...
On a Basic heads and cam combo in a daily driver...the preset tables in the Ls1 global setup usually works great..
But only if you get the base fuel table correct to begin with.
12-09-2014, 08:15 PM
#4
The car dying when you put it into gear may be IAC related..
Make sure your iac is at 5-10% when in gear at idle..
It should idle in neutral or park at 0%-3%
I like to make it just barely flicker 1% or 2% at idle in neutral
If all else fails after that..you may need to play with the iac settings..try using "fast" instead of the lsx setting
Or even play with the custom settings and play with the PID terms if you understand how they work.
Make sure your iac is at 5-10% when in gear at idle..
It should idle in neutral or park at 0%-3%
I like to make it just barely flicker 1% or 2% at idle in neutral
If all else fails after that..you may need to play with the iac settings..try using "fast" instead of the lsx setting
Or even play with the custom settings and play with the PID terms if you understand how they work.