[txpat3]

So, my 5.0 seems to be having difficulty starting the past couple of days. No issues with start-up until now. Yesterday I noticed that starting the car seemed to take 1-2 seconds longer than usual and the gauges all bounce/tick at the bottom for 3-4 seconds while the gauge lights flicker. After this everything seems normal and no other driving issues have occurred.

Issue seems to be getting worse by the day... started the car this morning and the engine cranked 3-4 times before turning over. At this rate it feels like given a few more days, the car won't start at all.

Help me AFM! Any ideas as to the diagnosis? Has anyone else experienced this problem?

 

[dusman59]

I have been thinking how long my battery will last. The heat does a number on them in our locations. Maybe your battery is starting to show signs of weakness.

 

[5.0 Coyote]

I would drive your Mustang to your Ford Dealer and have it checked out, before you have to have it towed to your Ford Dealer because it WON"T start,I just had my battery replaced in my 2011 early build GT, cause of its age,and I don"t like to walk.

 

[txpat3]

Good suggestions!! Thank you. I will have the battery tested to see if that is the culprit. Mine is an early 2011 build also and the battery has never been replaced.

 

[tntoy]

The battery is my initial suspicion.

When your car's voltage drops below 10-11 volts under the load of the starter, you're getting a voltage low enough that the computers don't operate on it, and like the gauge cluster, they kinda have to reboot mid-cranking. That's why the needles cycle like you cut the key off then right back on.

Simplest test for this? Jump start the car and see if it still does this without the battery voltage dropping. If that fixes it, it's time for a battery.

 

[txpat3]

Well, your suspicions were correct! Attempted to leave work last night and the battery was dead. Jumped it real quick and went straight to get a new battery. Problem solved! :bigthumbsup

 

[tntoy]

Happy to have helped. (Almost)

 

[Kona stang10]

What battery did you get?

 

[cudaman]

$25 Schmacher trickle charger or Battery Tender Jr will keep the new battery always up-to-snuff when you aren't riding the Coyote. Mine sits in the garage with the battery tender on it when not it use. Religiously fires in 2 or 3 cranks like brand new.

 

[domesticpower]

I have an early build 2012 Boss 302 and was actually disappointed at the age of the battery. I had to replace it a few weeks ago because it wouldn't hold charge. It was under warranty so it didn't bother me so much but being only 3 years old seems young for a battery to go. Glad you got it figured out OP.

 

[Hypnotoad]

Honestly 3 years seems to be about average. My old Mitsubishi Outlander was a 3 year lease, and at 2.5 years in, the battery was DOA and wouldn't take a charge; and it had only been run down once before when my mom left the lights on. My previous Mazda CX-7 was taking longer to start last winter, so I had to put a new battery in (was just over 3 years old) and that had never had the battery drained. I guess that's just what their life expectancy is any more.

 

[tntoy]

The longer a vehicle sits, the shorter the battery life will be. Automotive batteries are meant to live their life with a full charge at all times. As soon as you use it to crank the car, it is immediately topped off by the alternator.

If your car sits a few days during the week often, and you drive something else to work whenever it rains all week? You'll find your battery will need replaced much sooner than someone who drives his car every day and never lets it get low.

 

[5.0 Coyote]

The longer a vehicle sits, the shorter the battery life will be. Automotive batteries are meant to live their life with a full charge at all times. As soon as you use it to crank the car, it is immediately topped off by the alternator.

If your car sits a few days during the week often, and you drive something else to work whenever it rains all week? You'll find your battery will need replaced much sooner than someone who drives his car every day and never lets it get low.

The solution to this problem is a float charger,my 2011 GT has only 14000 miles on it,I just changed out my battery because it was almost 5 years old, but still held up under a load test,just didn't want to take any chances of a no start condition.

 

[cudaman]

The solution to this problem is a float charger,my 2011 GT has only 14000 miles on it,I just changed out my battery because it was almost 5 years old, but still held up under a load test,just didn't want to take any chances of a no start condition.

Same as what I tried to express in post #9. Each of my rides sets on a floating trickle charger while I use the one for that week. Haven't had a battery fail/not-charge in more than 7 years.

 

[kamakaz1961]

So, my 5.0 seems to be having difficulty starting the past couple of days. No issues with start-up until now. Yesterday I noticed that starting the car seemed to take 1-2 seconds longer than usual and the gauges all bounce/tick at the bottom for 3-4 seconds while the gauge lights flicker. After this everything seems normal and no other driving issues have occurred.

Issue seems to be getting worse by the day... started the car this morning and the engine cranked 3-4 times before turning over. At this rate it feels like given a few more days, the car won't start at all.

Help me AFM! Any ideas as to the diagnosis? Has anyone else experienced this problem?

I recently had the same issue. I replaced the battery and the problem went away. Sad thing is when I took it to the dealer they checked the charge and said it was OK...ie the charging was fine. IMO the factory batteries do not last more than 2 yrs. So I replaced the battery myself (real easy). I would look into replacing the battery.

 

[Senderofan]

I have an early build 2012 Boss 302 and was actually disappointed at the age of the battery. I had to replace it a few weeks ago because it wouldn't hold charge. It was under warranty so it didn't bother me so much but being only 3 years old seems young for a battery to go. Glad you got it figured out OP.

Had to replace my battery in my Boss this past spring. So.....something on the order of two years old or less. We have a lightened version ( by one pound ) of the battery that they put in the GT. Not sure where they found areas to lighten the battery...but perhaps it makes our batteries a little less robust.

I have an Odessee in mine...don't care about a little extra weight....want a robust battery that won't leave me stranded.

Wayne