So I made changed to my comp. and played with timing and also changed gear ratio and tire size. The computer I have in there was one from Bryan @pcmforless. Well the vin on that comp is for a a caprice classic wagon with an auto and the standard gears and tires for that car. Whats wierd is that I loaded the changes (changed tranny to M6, 3.73's, 275/40-17's along with the timing table changes i made too) and loaded. the car ran better so i knew the changes went in. Now, I scan the comp a day later to see what program is on there and the changes were put back to the original (except for the timing)! Do I need to clear memory or something. How do i get it so the tune stays?

 

how can you scan the car a see what program is in it. do you mean you read the pcm to see whats in it.

make the changes agian. and be sure you hit the calculate buttom then the apply button. you prbably didnt hit the apply button. just try it agin.

you are using tunercat right.

 

Yes sir I do have tunercat and i did read the ecm (pcm, ecu, whatever we wanna call it). I did indeed hit calculate and apply. I then made my timing changes and saved the program. I then "programmed" my ecm. The timing stayed, but the 3.73's and such didnt. I'll have to do it again like you said and see if it sticks. Thanks.