hello am new to this so sorry if i sound dense.
need help after batterychange idle speed is very low,it was before the new battery but now the car stalls aswell,would be grateful for any help .

the idle stepper motor may need to be reset as it has forgot its working parameters due to battery power interuption.some mitsubishis have a specific procedure to reset them stepper motor but others just require a bit of driving to relearn.I believe there are posts in this forum about both.as for the low idle speed I would clean the throttle body out as it may be carboning up and starving the vehicle from air at idle.easy to see by opening the throttle valve and looking for black sooty deposits.easiest way to clean it is removal.fairly simple as it is usually less than 6 bolts.one trick is to clamp off the coolant lines going in and out of the throttle body.this will save loads of time and eliminate the need to drain the coolant system

Not disrespecting Conan's knowledge or anything, as he def knows his stuff about the Carisma! But you may be able to get away with just giving the throttle body a quick clean with some carburrettor cleaner spray. You don't even need to fully remove it, just pull off the air intake tube, and undo the four nuts to detach the throttle body from the engine block. Then give it a liberal spraying of the cleaner (can get from halfords for a fiver) whilst waggling the throttle open and shut with the cable.

This was enough to cure a problem with my carisma gdi where it would not start when cold and would stall when idling!

be careful not to use carb spray as it can eat away the protective coating on many injection units-most sprays now are injection cleaners and are safe for both injection and carbs.the only reason I suggest removal is that the deposits form on the back of the butterfly and inside the throttle body unit.removal is the only way to completely remove the deposits.your way will work but the result is a much shorter run time before it clogs up again.If you choose to do the cleaning while it is still bolted on then be sure to allow the vehicle to sit for at least 15 minutes to allow the cleaner to evaporate following the cleaning as it may cause running faults or may not start after.good luck

On checking the spray I got, it is actually called 'Wynns Fuel Injector Intake and Carb Cleaner', so it sounds like the stuff you're on about Conan I'm relieved to say.

it's definitely true that my method is the lazy man's approach :P It takes no more than 30 minutes to do, and has lasted another year without the stalling on idle coming back, in fact I've just done it again before it starts getting cold again! If you remove the four bolts on the throttle body you can pull it away from the engine block enough to clean the back of the butterfly a little bit. It also means the excess cleaner doesn't all run into the engine which might not be a great idea.

But maybe I'll have to remove it and give it a good bath if the cold start problem recurs this winter.

Changing the battery has reset the EMU.
It's stalling because the base idle is too low - when it gets too low the engine cuts out as a 'safety feature' (which was greatly appreciated when it did it to me half way across the A5).
I had the same problem, caused by my battery being disconnected.

To reset the base idle;
disconnect battery leads and short together for a minute or so
reconnect
run engine at idle for 10 minutes with no electrics on
turn off
restart with air con on full (or all electrics on), run for 10 minutes
restart
take for a run to smooth it out (it took me a while before it was running right, maybe 150 miles - a long motorway run is ideal)

Your throttle body is probably coked up as well - I have mine cleaned each service.

If you try either of the TB cleaning methods are there any gaskets you need to replace or anything else? Keen to give it a try at the weekend but don't want to be halfway through where I realise I need some bits.
Cheers

I followed firefly's instructions exactly, (my favorite part was the 150 mile run,) and it worked perfectly. I am very thankful that I did not have to pay a mechanic to fix something so simple. Thanks!

I know I asked this question before, but can someone show in through pics what the throttle body is and how to clean it.

I removed the four screws at each side for my carisma. there was this metal like thing in the part that I removed and it was attached to some electric wire. As Conan stated before, I removed the coolant lines before.

Once all of this was done. The piece that the other piece attached with four bolts, is that the throttle body. Its like a long silver thing, quite round and shallow on the inside. Is that the thing were the cleaner is sprayed into? and is that the piece that Conan suggested removing and cleaning for more effective run?

thanks