Changed battery, now no idle!

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Well I changed the battery on my 02 Camry and now the idle goes to 0 and car stalls out if I take foot off gas. I put a battery minder (9V battery) into cigarette lighter but it did not hold computer memory. I drove the car for a couple of hours hoping it would relearn idle...no dice. Some say it needs throttle body cleaning and others say the computer needs to be reflashed Any thoughts??
 
When I had my Trailblazer - over at Trailvoy it was well known that if you were replacing or disconnected a battery and had a dirty throttle body you would have severe idle problems.
What happens is the "computer" learns to compensate for the dirty throttle body over time, but when you replace the battery it goes back to factory settings. It's cheap and easy to do.
 
Removing and installing a battery should not make the car "forget how to idle" That is programed into the ECU and is a default. It could be that while taking the battery out a termanal hit a peice of metal and shorted out a fuse to the ECU.

Its really hard to say. All I can say, is the ECU did not forget how to idle. Its a Toyota so I can tell you its most likely a simple fix.

Jeff
 
Originally Posted By: Jeffs2006EvoIX
It could be that while taking the battery out a termanal hit a peice of metal and shorted out a fuse to the ECU.


That could have also damaged the ECU. But that's extremely unlikely to be the case, as the car would have more severe problems than no idle with either a blown ECU fuse or a damaged ECU.

Quote:
Removing and installing a battery should not make the car "forget how to idle" That is programed into the ECU and is a default.


I can't speak for the sophistication of Toyota ECUs, but their competition has ECUs that are capable of learning idle characteristics (typically to compensate as the idle air control valve gets dirty) and these have been around for over 20 years.
 
Thanx all 4 your advice. Now I am armed when I go to the stealership in the morning. Can you guys give me a ballpark cost for throttlebody cleaning, and do I need to change the oil after it's cleaned?
 
Originally Posted By: motts
Thanx all 4 your advice. Now I am armed when I go to the stealership in the morning. Can you guys give me a ballpark cost for throttlebody cleaning, and do I need to change the oil after it's cleaned?


I can tell you that it takes about 15 minutes and about $5 for a can of cleaning spray.

How much the stealership will charge you for this is hard to say. They may end up replacing the idle air control valve instead of trying to clean it. I'd suggest bringing a credit card with lots of room on it.
 
Originally Posted By: brianl703
Originally Posted By: Jeffs2006EvoIX
It could be that while taking the battery out a termanal hit a peice of metal and shorted out a fuse to the ECU.


That could have also damaged the ECU. But that's extremely unlikely to be the case, as the car would have more severe problems than no idle with either a blown ECU fuse or a damaged ECU.

Quote:
Removing and installing a battery should not make the car "forget how to idle" That is programed into the ECU and is a default.


I can't speak for the sophistication of Toyota ECUs, but their competition has ECUs that are capable of learning idle characteristics (typically to compensate as the idle air control valve gets dirty) and these have been around for over 20 years.


Exactly! Maybe Toyota ECU's aren't as sophisticated as say GM's?
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Seriously I've seen this happen a lot especially on GM vehicles and 99 percent of the time a 5.00 can of carb cleaner and about 15 - 30 minutes of time cleaning the throttle body will fix the problem.
 
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Make sure you didn't knock a hose off or loose on the flex tube from the air filter housing to the throttle body while changing the battery.
Look carefully,even tugging lightly and make sure they are all connected.
 
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Just had a Camry in the Subaru shop last week. Same deal. We replaced the battery and it didn't idle. Drove it up and down the highway with no results. We took the intake hose off the throttle body and cleaned everything thoroughly. Ran perfectly and idled smooth as glass after that. There's something to be said for keeping throttle plates and bores clean on EFI cars!!
 
I had the throttlebody cleaned at Toyota ($135). No issues now. They said a new one is $1200!
 
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