Hard to start because of battery change?

My daughter has a '00 Mirage. She got new tires and a new battery today. Tech had a hard time starting it after new battery installed. Said it was because the computer "forgot" settings and that Mitsus are known for this. I've had the cables off each year to clean the terminals and this never happened before. Could it be that the battery was disconnected for a longer period that this occurred? I've had batteries out of my wife's Camry and my Eldo for longer periods with nothing more than the radio and clock losing settings. Is this something peculiar to Mitsus as the tech stated? TIA DFB

Reply to
NickySantoro
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All ECU's have a "learning" curve. If it was a one time thing, I wouldn't worry about it. The mitsu actually has a big capacitor in the radio that should last about 20 mins without needing to re-enter the code or settings. The ECU is designed to reset immediately (ok...3 secs). I know your Chevy is designed to hold the ECU power longer, but I'm not sure about your Toyota. If it get's better in one or two drive cycles, I wouldn't worry.....It just means you daughter's O2 sensor is getting old.

Reply to
Nobody U. Know

Does the engine stall or run very slow on tickover ?

Reply to
Jonny

Thanks for the response. She said that it started and ran fine on subsequent attempts, just like normal. That's the fooler, why it was bitchy on the first start after the new battery install and why the tech said this is common in Mitsus. First time ever I've heard that.

Reply to
NickySantoro

Check the butterfly valve , (Thats the one in the inlet manifold) What you have to do is clean round its seating. What happens is the onboard ECU remembers the position of the butterfly (Via the TPS,) But after you disconnect the battery it resets the position to when the engine was brand new. This means that after you have driven a few thousand miles the butterfly is in a different position from new, due to soot gum etc . and will be slightly open giving hesitation,slow idle,Even start problems. The ECU will have compensated for this by making adjustments to the idle/inj control.

Take off the rubber tube between the air cleaner and the inlet manifold then peer in ,my guess is you will find its gummed up and black in colour . Clean round the brass butterfly valve,( use carburettor cleaner) then disconnect the battery once again ,should be ok after this. Any Mitsu Tech would have known this. i would find another garage . Some other makes of car have the same configuration but instead of just disconnecting the battery demand an expensive visit to a dealer for reseting via PC equipment. Im glad i have a Mitsubishi .

Reply to
Jonny

Again, many thanks. Your explanation makes perfect sense. I've printed it out for future reference. My '93 Eldo is the same. If I clean the TB, I disconnect the battery for a minute to reset to default or do the idle learn procedure.

Reply to
NickySantoro

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