[eaxebx]

Car: 2013 Ford Focus SE Gas 2.0L
Symptoms:
1) battery light turns on about 1 minute after the car is turned on, stays on as the car is driven.
2) low MPG after the car is turned on, MPG improves as the car is driven.
3) engine stalls, very low power from engine for about 10-15 minutes after car is turned on, then the engine performance returns to normal.
4) car battery tested okay, no parasitic current loss, battery voltage 12.4 Volts after 2 days of non-driving.
5) car battery compartment had rain water, bottom of the battery was submerged in rain water (unsure for how long), but autozone and my own testing of the battery all reported battery is okay.
6) replaced spark plugs, didn't fix the problem
7) full battery voltage is 12.8V after trickle charge, after engine is turned on, voltage across battery terminal is 14.4 V (in normal range), voltage across battery terminal didn't drop below 14 V at 2000 RPM+AC+light+audio all turned on. So Alternator seems to work okay.
8) Has a P0456 very small leak code (replaced evap canister, didn't fix the problem), possibly the internal valve is not shut.
8) autozone checked battery, starter, alternator, all in good shape.

I am out of ideas. Any help is appreciated, can provide other information.

Thanks!

 

[pbfoot]

12.4 volts after sitting 2 days is not good. 12.65 is what you should see. Get the battery load tested. Battery system management has to be reset after a new battery is installed.

 

[pbfoot]

As far as your other issue, sounds like a purge valve issue.

 

[zrx212]

I had a issue with overcharging, that killed my battery, it had actually overheated the battery, causing it to boil acid over, fortunately it was contained by the battery box, my light was also on, after a lot of looking/testing found out small wire at alternator connector was internally broken, intermittent contact, it was routed around water hose that was stretching it, etc. I was able to repair with solder, etc. Had to install new negative lead assy, new battery and wash/neutralize acid, etc. About $250 for a diy, better than dealer cost.

 

[eaxebx]

The battery is fine under load test. I retested the voltage yesterday (4 days after sitting in the car), it came back 12.56 V which is really good. I think my previous measurement (12.4V) was not correct, I didn't push the test lead from the multimeter hard enough into the metal contact. Again everything about the battery seems okay, however I should not completely eliminate it from the equation because it was submerged in rain puddle for a while.

I also think the P0456 very small leak is may be related to the electric system and it's caused by the problem. Again replacing the purge valve canister didn't fix the engine code.

Do you all think this is most likely an alternator problem? Fixing the alternator on the 2013 ford focus is not fun. The part is expensive and the location of the alternator is hideous.

 

[eaxebx]

Also I would be happy to fix this problem if it only costs $250.

 

[zrx212]

Need to make sure the small signal wire at alternator has voltage and it's not broken, there's also a issue with the grill shutters affecting charging system. Video explains best

 

[eaxebx]

Thanks, I'll check the video. There is more information I forgot add, the car was sitting in the winter rain/snow. I did drive the car, about once a week, 1 hour drive. Thinking about this it's possible, that the battery is getting drained out and that put stress on the alternator and damaged the alternator.

 

[eaxebx]

Oh yeah, that was the first thing I checked under the car, in my case the connection was all very good. I was very disappointed when I found out that was not the cause of my battery light problem.

 

[eaxebx]

The thing that puzzles me the most is this:

When I start the car, everything feels good, engine feels good, etc... then after 10 seconds, you can feel the engine becomes sluggish, battery light comes, the mileage per gallon reading steadily decreases..

Wait for 5-10 minutes, everything feels normal again, engine becomes smooth, MPG steadily increases, but the battery light remains on...

So puzzling.

 

[Honey Badger]

I'd start by replacing the battery. I have seen several cases where the battery tests "good" on the bench but it doesn't work in the car. I suspect it's because many bench testers are old fashioned, they don't put the battery though it's paces like a modern car does. This part is a dead giveaway:

3) engine stalls, very low power from engine for about 10-15 minutes after car is turned on, then the engine performance returns to normal.

In new cars they avoid running the alternator to save fuel, especially at low engine speeds and when the engine is cold. Even if the voltage drops below the point where it can effectively run the electronics. Coupled with lots of high current draws on the system for electric power steering and whatnot. In one example both me and the dealer spent several hours troubleshooting an issue where the battery would start the car just fine, but once running would lose power and stumble. That battery tested good at AutoZone the very same day I was working on it.

Where I'm at the ford dealer charges $90 just to look at your car, which is most of the way to a new battery. And like you said, you're definitely willing to spend $250 to get this sorted out.

You can reset the battery management system with forscan or a Nintendo cheat code, if you search YouTube you should be able to find it.

I would reiterate what pbfoot said about the purge valve, that will cause the car to stall out as well. If the battery doesn't fix it, swap that out. It's super easy, right on top of the engine. Your car will need a new one at some point if not now.

 

[eaxebx]

Yes, I am really leaning towards a battery problem (sitting in that rain puddle was no good). I've visually inspected the alternator a few times and when the car runs, I have a steady 14.4 V at the battery terminals. I think the alternator is fine.

Just today I checked the battery again and it went to 35% SOC using a battery tester. Combined what you mentioned about how the electronics are stressing out the battery, I'm fairly convinced that the battery is the problem.

 

[eaxebx]

Okay, I put in a new battery, light is still up. MPG still goes down and up. I have 2 codes U012D, U0284 the grill shutter related code, visual inspection shows the grill shutter is closed and won't open (I pushed it).

Now the good news, the engine feels responsive when turned on, it no longer feels it's on low power, it feels responsive. More importantly the smell of unburnt gas disappeared. Previously there is a thick smell of gas right after engine is turned on, it's gone!

I have a feeling that the battery light, the new engine codes and MPG numbers are caused by some other problems. The real issue was the battery (engine feels responsive and there is no longer smell of unburnt gas).

 

[Honey Badger]

Ok, sounds like you have multiple problems. You might have a bad battery current sensor. If you had water sitting in the battery box I'd make sure all the terminals and contacts are free of corrosion too.

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