high octane/ low octan.e tables
#1
10 Second Club
Thread Starter
iTrader: (27)
Join Date: Sep 2008
Location: Lake Tapps, WA
Posts: 2,229
Likes: 0
Received 0 Likes
on
0 Posts
high octane/ low octan.e tables
How does the PCM decide which table it's using? Is it by knock? Also on hptuners is there a method or device to make sure your running the high octane tables?
Thanks this is all new to me
Thanks this is all new to me
#4
TECH Addict
iTrader: (4)
You should only do this if you're tuning the VE tables (and thus have the MAF failed), and copy them back when you're done. If you're just copying them and leaving them, thats very irresponsible in the tune as it's not leaving the PCM any choice when something does go wrong.
#5
10 Second Club
Thread Starter
iTrader: (27)
Join Date: Sep 2008
Location: Lake Tapps, WA
Posts: 2,229
Likes: 0
Received 0 Likes
on
0 Posts
So I would only be using the low octane table if I had a failure, certain codes and knock? If you where running on the low table would the pcm automatically switch to high octane if the failure or condition changed?
#6
You should only do this if you're tuning the VE tables (and thus have the MAF failed), and copy them back when you're done. If you're just copying them and leaving them, thats very irresponsible in the tune as it's not leaving the PCM any choice when something does go wrong.
#7
TECH Addict
iTrader: (4)
Knock retard pulls timing for a set time, and then gives it back, and with bad gas, that will result in knock again and again and again...with proper functioning low octane tables, when the car knocks enough, the PCM will give up and run solely off the low octane tables until you fill the tank...then it will try again...knock retard can't function until it see's knock...so it has to let it come back and knock...what would you rather have your engine do?
Trending Topics
#8
TECH Enthusiast
Join Date: Nov 2006
Location: Katherine N.T Australia
Posts: 620
Likes: 0
Received 0 Likes
on
0 Posts
Think of the initial detection of knock in the same way as STFT's. They'll fix it for the moment but wont remember for later. Then think of Adaptive Spark (The blend between high and low spark tables) as LTFT's.. That's about as simple a description as I can think of off hand.
If you don't know how fuel trims work, that description probably wont help you.
If you don't know how fuel trims work, that description probably wont help you.