Anyone have this happen them?

I have an '07 manual sport with about 44k miles. So, went with the advice and replaced the stock battery with a more common 51R battery. Everything is fine, but I swear that right after the battery was swapped I noticed that when the car is in gear it's running rough.

Thanks!

Mike

 

You sure you didn't accidentally knock a vacuum line loose or something? Changing a battery shouldn't affect the way the engine runs.

I'd double check to make sure all the lines around that area are connected properly, make sure any grounds you've loosened are snug, and check if the intake for any unmetered air that is getting in after the mass airflow sensor just in case you knocked it loose during battery removal.

 

A new battery is not fully charged so there is a higher load on the alternator trying to charge the battery. The fuel trims are being re made too, so it should run better in a few days.

 

2 thoughts, first, if the 'new' battery was not fully charged your alternator may be carryingheavy load.
gas mileage lower than normal good indication?
second, is the 51R battery hefty enough to carry the electrical load of your Fit especially if you have BIG musical stuff.

 

Ill bet the ecu just needs to relearn the fuel/air trims and such. When you disconnect the battery, it loses that stuff and needs to relearn by running and checking sensors. Usually takes about 15-20 minutes

 

i had to replace my stock battery due to it dying on me when the car was off, i had mine swapped by the dealership i payed $147 after they replaced it the car ran smoother so i will say that changing the battery does in fact help the way the car feels

 

The 51r has the potential to make contact with the airbox when the engine is under a load. Maybe that contact loosened something.

 

Do the idle relearn procedure if not allready done!

Marko!

 

I have the same problem. I've replaced it with Kirkland 51R at Costco for $66. What a bargain. However, after replacing it cars been idling rough. It's been 3days already with good driving and it's the same. My original battery lasted for 65k and it's been very weak to start and sometimes won't start at all. I don't think it's the matter of relearning, because when original battery was dying I had it disconnected many times and when it was charged it didn't feel any different. However, putting putting in new battery sure made it different.
I tried the relearn procedure reving to 3k until fan come on and idling for 10min...
I wonder if the voltage difference is the problem.

 

Voltage is determined by the alternator. I'd check to see if the battery is rubbing against something.

 

It's not rubbing on anything. There is tiny space and even if it were to contact it couldn't do what it's doing now.

 

did you do the idle relearn?

 

When I swapped in the 51R in my 08 i had to buy a terminal post shim. Here is a link to what i mean. Lynx/Battery post shim (07769) | Battery Terminal End and Adapter | AutoZone.com

maybe you are not getting a good connection, for me it was the positive terminal that was smaller. good luck.

 

Yes it can. Just because the alternator is supposed to have an output of 13.2 vdc doesn't mean it does. Have a reliable shop check the running voltage; if its lower than 12 volts there is a good reason for rough running. It could be a fault in the new battery thats loasding the system and reducing the voltage output OR the current, which will also result in rough running. If it idles OK but roughs up when the load on the engine increases I bet there is a voltage/current probnlem.