Hey all ... I've just recently bought myself a 97 magna s/wagon ... not the most exciting thing but a lot nicer than the van it replaces! :badgrin:

Anyways, car was running fine but cranked slowly when starting up, esp after a few days without use. So, down to autobarn I go and buy meself a brand new battery. It seemed to hold 12.5v without charging so out goes the old smelly battery and in with the new. Go for a drive around the block and it starts stalling when slowing down, seems not to hold idle and is very reticent to kick down gears when slowing down.

I read up on here about the problems with the ecu resetting itself. Ok, no dramas, just drive it around for a while. So I've driven it around on and off for a couple of days but still no dice, still wants to stall when slowing right down. I've driven a reasonable amount in the last couple of days, mainly just around the area but well more than an hour or so.

I've been driving around preloading the throttle when braking to stop from stalling, which makes the down changes rather clunky and forceful, and its really starting to peeve me off. :rant:

Anything I can do to fix this or is this a case of taking to the local ultratune/dealership/mystic voodoo doctor?

Dunno if this will help or not but from what i read on here after you connect the battery i believe you are supposed to let it idle for a good ten to fifteen minutes to let the ecu do its thing ...................

Yer like slug said

Disconnect the battery again and start from scratch, Reconnect it then start the car and let her idle for a good 15 - 20 min at least

Cheers

Heath

Don't idle it, no.

The Mitsu service technique after disconnecting 12V power is to start it up and
immediately rev it to 1500 rpm then hold it there for 30-60 secs.

When you lift off afterwards it should know how to idle again.

Magnette, where did you hear this from?

I really want to know what the correct procedure is when disconnecting and reconnecting the battery.

This is been taken from Mitsu service department manual.

Sweet mate :D Thanks for that!

Sad to say, you have to take to mitsu dealer and get the computer retuned, it's been reset back to factory settings.
Happened to my dad's mitsu when he put in a new battery.
I don't think it's expensive.

I think the computer has a battery of it's own but won't hold a charge if the main one is kicking the bucket.

Magnette, where did you hear this from?

I really want to know what the correct procedure is when disconnecting and reconnecting the battery.

Service mgr at Mitsu dealer Brandon Park told me that 10+ yrs ago, same echo'd by another mechanic who knows everything there is to know on Magnas and Corolla/Camrys.

Have done it to TN & a CC Lancer, both worked - Lancer was particularly undrivable without idle. Another friend did it on his TR too, also good.

Haven't had need to try it on a 3rd gen yet, but they do use a similar ISR design.

This is been taken from Mitsu service department manual.
umm... if your ISR has gotten amnesia, the CAR WON'T IDLE... :doubt:

Hi guys - thanks for the help.

I pulled the neg terminal off for an hour last night and, as recommended, started the car and let it idle for 20 minutes. I took it for a drive a while later and it seems to be happy holding its idle now. I'll need to take it for a longer drive to make sure, but I'm fairly sure that it would start stalling fairly quickly, so it all looks promising. :cool:

Now all I need to do is call mitsi and get the security code for the radio, since I don't have the original owners manual :P

Thanks for your help! :)

if still encountering problems nmilne do see youre mistu dealer na d get your base settings adjusted. this is the correct mitsu procedure when you have the mut II obviously. what happens is the throttle body starts to become resriced over the years and the ecu and isc motor compensates for slight gumming. when you replace the battery the factory default position for isc position is picked causing stalling. solution 1 is to just reset base settings or solution 2 is to clean throttle body out......just check throttle body as its not uncommon to find they are fairly gummed when they have some klms on them.
hope to have been of help

cheers mon

Cheers mate - i'll have that looked into next service!