When I make changes to the idle parameters does the PCM need a learn time?
Thread Starter
Joined: Apr 2003
Posts: 2,597
Likes: 4
From: Lawrenceville, GA
When I make changes to the idle parameters does the PCM need a learn time? I have a question after cam install. Already went thru the setting of the TB screw. When I make changes to the idle parameters does the PCM need a learn time? How long should I wait before each change? I did 21 flashes today and ended up going back to the third one. If the PCM needs to relearn I will have to start all over. Right now it idles OK after it finds idle. It still surges up and down. I guess I just need to keep trying to get it right. I just wanted to make sure the PCM does not need learn time.
Thanks,
Bill
Thanks,
Bill
Thread Starter
Joined: Apr 2003
Posts: 2,597
Likes: 4
From: Lawrenceville, GA
Before the cam the LT's were all negative. I am just trying to get the thing to idle in gear without surging or going into cruise control.
Since I have changed my VE table and timing table I guess I need to do some relearning to see where the LT and ST are now.
Thanks,
Bill
Since I have changed my VE table and timing table I guess I need to do some relearning to see where the LT and ST are now.
Thanks,
Bill
FormerVendor
Joined: Jan 2003
Posts: 525
Likes: 0
From: Melbourne, Australia
LTIT = Long Term Idle Trim
LTFT = Long Term Fuel Trim
two entirely different beasts!!
when you change anything related to idle RPM or idle airflow, you must let your LTITs settle out to a steady state value (also check they are not hitting the calibration limits). LTIT and STIT are something we added to the scanner with v1.6.0. You can find them (and a bunch of other idle PIDs) under "Engine -> Idle" in the insert PID list.
Chris...
LTFT = Long Term Fuel Trim
two entirely different beasts!!
when you change anything related to idle RPM or idle airflow, you must let your LTITs settle out to a steady state value (also check they are not hitting the calibration limits). LTIT and STIT are something we added to the scanner with v1.6.0. You can find them (and a bunch of other idle PIDs) under "Engine -> Idle" in the insert PID list.
Chris...
Thread Starter
Joined: Apr 2003
Posts: 2,597
Likes: 4
From: Lawrenceville, GA
Originally Posted by Another_User
Your LTITs need to re-learn. You need to log LTITs and STITs before making any base running airflow changes. LTITs can screw you up really badly.
Bill
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TECH Addict
Joined: Feb 2004
Posts: 2,826
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Originally Posted by gameover
LTIT = Long Term Idle Trim
LTFT = Long Term Fuel Trim
two entirely different beasts!!
when you change anything related to idle RPM or idle airflow, you must let your LTITs settle out to a steady state value (also check they are not hitting the calibration limits). LTIT and STIT are something we added to the scanner with v1.6.0. You can find them (and a bunch of other idle PIDs) under "Engine -> Idle" in the insert PID list.
Chris...
LTFT = Long Term Fuel Trim
two entirely different beasts!!
when you change anything related to idle RPM or idle airflow, you must let your LTITs settle out to a steady state value (also check they are not hitting the calibration limits). LTIT and STIT are something we added to the scanner with v1.6.0. You can find them (and a bunch of other idle PIDs) under "Engine -> Idle" in the insert PID list.
Chris...