how long does it take PCM to learn?
Thread Starter
12 Second Club
iTrader: (2)
Joined: Jan 2004
Posts: 515
Likes: 1
From: Long Island, NY
how long does it take PCM to learn? have the Predator tuner and just removed the perf. tune and returned the stock tune. the car has been running a little rough, w a little KR and I'm curious to see what happens without the tune. my question - how many miles does it take for my car to really get back to stock? 
Not really miles, how the long term trims learn is
by the magnitude of the short-term error and
the sime you spend in a cell. Cells like idle and
your most-common cruise points learn out quick
(by clock-on-the-wall time) but cells you use
seldom or briefly will take a longer while to get
their "time in the saddle" and smarten up. It
could be a week if you have very fixed driving
habits. Try and mix it up, more 1/4 to 1/2-throttle
acceleration for no reason. Predator seems to add
some PE with its tune and pulling it has probably
confused the higher-TPS cells lean.
by the magnitude of the short-term error and
the sime you spend in a cell. Cells like idle and
your most-common cruise points learn out quick
(by clock-on-the-wall time) but cells you use
seldom or briefly will take a longer while to get
their "time in the saddle" and smarten up. It
could be a week if you have very fixed driving
habits. Try and mix it up, more 1/4 to 1/2-throttle
acceleration for no reason. Predator seems to add
some PE with its tune and pulling it has probably
confused the higher-TPS cells lean.
Thread Starter
12 Second Club
iTrader: (2)
Joined: Jan 2004
Posts: 515
Likes: 1
From: Long Island, NY
Jimmyblue thanks for the info. I'm going to leave the factory tune in for a week and then after I get my headers and gears installed get a custom tune done from the predator guy and install it - does that sound like a good plan? If I'm still getting knock retard, should I mess with the timing (increase?) I know I should just go and have it dyno-tuned but I spent $400 on this Predator I want to give it a chance.....
