Will a Dynotune get un-learned?
Instructor
Joined: Oct 2002
Posts: 181
Likes: 0
From: Windham NH
Originally Posted by timf1954
If I go get an expensive dynotune, will the PCM do it's learning thing and eventually hose the tune?
There are adjustments that car makes as it drives around but these are all deltas from the hardcoded tables. Even that... they are limited changes. So things like timing remain fixed UNLESS the car is seeing knock and then it will change the timing TEMPORARILY. How much, how fast, and when it returns to the hardcoded table can also be set with a tune. Air/Fuel changes are made by the computer at run time under most conditions but again they come from a starting point which doesn't change. There are lot's of other little things they do at a tune such as Tourque reduction settings or shift settings (for autos) that will also not change but can enhance performance.
So the long and short of it is YES the car makes adjustments to normal "cruising" a/f ratios but a tune will help minimize those and get the optimal performance out of the car.
--Bill
Race Director
Joined: Jan 2002
Posts: 19,557
Likes: 1,470
From: I love you & miss you Linda
2017 C7 of the Year Finalist
St. Jude Contributor
You got a good reply there above from bletour2001!
One other thing you may want to know (if you do not know this already)
If you take your car to the dealer for warranty work, they may or most likely will flash your PCM to update it to the "latest & greatest" that GM has to offer at the time.
You should advise your dealer Mechanic that you've had a tune and NOT to flash the PCM. If he does flash it, it will overwrite the entire tune.
Another safeguard is to be sure the tuner has a saved copy of what he did to your car so he could restore it in the event of an inadvertant overwrite.
One other thing you may want to know (if you do not know this already)
If you take your car to the dealer for warranty work, they may or most likely will flash your PCM to update it to the "latest & greatest" that GM has to offer at the time.
You should advise your dealer Mechanic that you've had a tune and NOT to flash the PCM. If he does flash it, it will overwrite the entire tune.
Another safeguard is to be sure the tuner has a saved copy of what he did to your car so he could restore it in the event of an inadvertant overwrite.
