I heard somewhere that if have a hypertech programmer and you have any engine work done to your truck, you have to program back to factory settings before having the work done. I"m getting ready to put a high flow cat on my truck and was wondering if i should de-program it just for that.

Everyone else who has a high flow cat, what difference did you notice with gas mileage and HP?

 

Sorry for the double post but...i went ahead and got the high flow cat already. I noticed the overhead computer reading out better gas mileage, will run a few tanks through for a more accurate average. I de-programmed it then reprogrammed it to be on teh safe side as far as teh Hypertech goes. I also noticed a nice little rumble as the motor racks off....

so i guess my next 2 steps are a K&N air filter adn a Fastman and I think I'm done for this year.

 

mostly when there talking about getting work done they mean taking it to the dealer where they would hook it up to the computer and that combo could kill your pcm.

 

aah ok. thanks. i noticed the first time i programmed it, it had spark knock for a few miles then it went away....and i just reprogrammed it and its the same thing. i guess it adjusts itself over time.

 

sorry for the double-post again but as soon as i put the high flow cat on i have a slight hesitation on startup....kinda like a sputter but not really..... could it be that i dont have a K&N?