Hello to all,

I apologize if this is a topic that has been previously discussed, however, I've searched and have been unable to find something that addresses my concerns.


I have a 2010 Mazda3, 2.0L, ATX that requires a battery change, research on the net tells me that doing so will reset the ECU and will invariably cause issues (run rough and stall) as the ECU will think it's in a brand spanking new car. On the extreme end, it's suggested that I'd have to clean out the throttle body or simply have the ECU relearn by:

• With engine off, turn key in on position for 1 minute
• Key in off position for 1 minute
• Start engine and let idle for 15 minutes

Or I've also read that the ECU can relearn by simply:

• Start engine and let idle for 20 minutes without any accessories running
• Then turn on the AC, coldest setting with fan on high and let run for 15 minutes or so

I'm hoping that members can provide some insight on the above. I've had many cars in which I've changed many batteries and have never experienced issues.

 

Turn off the car, remove the key, close the doors, Remove & replace the battery, start it up, make sure the lights & a/c is off, let it idle for a minute or two, set radio stations, set clock, set auto window, drive away, done.

 

Gotta love it. Grim is right, of course. The only thing the engine relearns is idle strategy. The rest happens as you drive and you'll never feel a thing.

I get a chuckle out of the voodoo rituals some posts have. Turn the key on 3 times, hit the brakes, cycle the radio from AM to FM, wave a chicken foot over the spare tire.

 

Chicken foot? I thought it was a Monkey's foot you needed?

Also, what happens if you don't have a spare tyre, but have a " Tyre inflator kit"?

 

HA, try getting a monkey paw in the states these days. If you only have the inflator kit, you must circle an ostrich feather with the items in the kit and chant a Zulu love song. Americans switched to the chicken foot, less work.

 

The issue when changing the car battery is when and if you have a very dirty throttle body and the ECU has over time made adjustments to keep the engine running. Only at this time will the changing of your battery result in rough idle or failure to start. When this happens you will need to completely clean both sides of the throttle body