Procedure in changing chips

[Captain Mark]

I am going to experiment with a couple of chips this weekend. When you change the chips, do you disconnect the battery befor you do it? Do you unplug the ECM before you do it? Do you do both?

Thanks,

 

[turbot2112]

you can just unplug the orange wire under the hood by the battery that goes to the ecm.

 

[Captain Mark]

Thanks

 

[87T]

to unplug or not too

I have not unplugged the ecm for more than a year now, I have seen NO Ill efects at all, every time you unplug the computer has to go throuhg the learn processes all over again and you might think the chip you just put in was not to your liking when it could be that the ECM is still learning,,,,,

 

[JayC]

I usually change them with the car running.

 

[1of1035]

I just turn the car off and change it. Never had any problem and been doing it that way for a little over a year

 

[dennisL]

I change the chip in my car every 300 miles or 3 weeks whichever comes first. The important thing as to whether the battery should be disconnected or not is, if the air/fuel stuff in the new chip is similar to the old chip then just swap them.

However, if you've been using a "brand A chip" and want to test a "brand B chip", then you should disconnect the orange wire for the swap. After the swap, drive the car around town for 3 or 4 miles, then begin the evaluation of the new chip.

For a closed loop chip to learn fueling, you'll need to run
- warm/hot idle
- some 10 - 25 MPH driving (hopefully in stop/go traffic)
- several brief part-throttle accels
- finally, add a few miles of 3rd and 4th gear cruise
- bake in a 180 degree engine compartment for 30 minutes and shazam! your chip is all "learned-up".