So I just got my X3 from Don at Lasota Racing, and I read through the instructions on the "Ask me tuning questions" thread, but it doesn't quite make sense to me. The instructions were as follows:

Flash it with your new tune.
Dis-connect the battery
Headlights on
Ignition on
Wait at least 10 minutes.
Turn everything off
Re-connect the battery.

Start the motor and just let it idle until it reaches at least 170F (or 2-3 minutes if already hot)
Let the idle come down to where you have it set.
Then turn the AC on full blast and let it idle like that for a minute.

If you disconnect the battery, there is no power going to anything. How will this help reset the PCM? So you disconnect the battery, turn the headlight switch on, turn the ignition to "ON", keep it like that for ten minutes, then turn everything off and reconnect the battery? I don't really under stand the whole PCM thing, so maybe I just don't get it? Thanks for your help.

 

im not sure why it tells you to do that, I never did that with my X-Cal II. maybe ive been doing it wrong for all these years. hmm

 

You definitely don't have to do all that. Just put the tunes onto the tuner, plug the tuner into the OBD II port and do what the tuner tells you when it tells you to do it.

 

i have never heard of having to do all that with a programer.

not to get off topic but...
what was the price on it?

 

It was $379 with free shipping. $400 for two tunes, but $379 for one. Don had the tuner programmed and in the UPS box before the end of the day I ordered it. Now we have to see how it works...

 

wydopnthrtl said to do what the OP posted. The reason behind it was that transmission tweaks were not being re-tuned with just a quick flash. You need to do all of that to clear the capacitors in the pcm for the transmission tweaks to go through. A quicker way to do this would be to touch the negative battery cable to the positive battery terminal which will instantly clear the pcm, however I am not comfortable with that idea so I just do what the OP posted.

Oh and I have noticed that if you do not let it idle up to temp afterwards, it takes a lot longer for the engine to get to stoich or wherever you set the AF ratio.

 

good info, thanks for posting that!

 

I've never heard of doing any of that either. But sounds easy enough to go ahead and do just in case.

 

I ended up flashing the truck without doing all that, and it definitely improved power. I did let the truck idle for 5-10 minutes. I have a 5 speed and the truck is a 2001. I ended up calling Don @ Lasota and he said just flashing it would be fine since I don't have a KAM like older Rangers.