[SSDan]

Originally Posted by chovaz

Yep, fixed for me for a bit (over Florida winter, maybe a coincidence) but with hotter temps back, it's happened 3 times again already. Came back here to check new solutions...

Please read posts #288,289 and 290. My slow crank came back three months ago just as I predicted it would (way back on post # 16) once the battery started to fail. The 2016 and 2017 models need a strong battery (full cranking amps) and the lowest resistance possible through the circuit from the starter to the battery (extra ground cable gives that) to overcome a heat-soaked starter. I put in a fresh battery and my hot and cold cranks are strong again.

I knew my battery was going out as the voltmeter would stay at 14V the whole time I was driving for about 4 months before it failed. I don't drive the car much on long trips. Most trips are 30 minutes or less. With this car's charging system and an AGM battery those short trips are a recipe for a short battery life (3-4 years tops). I now use a battery tender between drives to keep the battery topped off.

Reading what I've posted today one could reason that a good battery is all that is needed. That is true for cold starts. But the heat-soaked hot starts need a good battery and the extra ground cable to keep that circuit resistance low or the starter will drag.

[chovaz]

Originally Posted by SSDan

Please read posts #288,289 and 290. My slow crank came back three months ago just as I predicted it would (way back on post # 16) once the battery started to fail. The 2016 and 2017 models need a strong battery (full cranking amps) and the lowest resistance possible through the circuit from the starter to the battery (extra ground cable gives that) to overcome a heat-soaked starter. I put in a fresh battery and my hot and cold cranks are strong again.

I knew my battery was going out as the voltmeter would stay at 14V the whole time I was driving for about 4 months before it failed. I don't drive the car much on long trips. Most trips are 30 minutes or less. With this car's charging system and an AGM battery those short trips are a recipe for a short battery life (3-4 years tops). I now use a battery tender between drives to keep the battery topped off.

Reading what I've posted today one could reason that a good battery is all that is needed. That is true for cold starts. But the heat-soaked hot starts need a good battery and the extra ground cable to keep that circuit resistance low or the starter will drag.

Thanks for the info...

Coincidentally for me.....my daughter was in an accident last year (November-ish), pretty soon after I had replaced the cable. The battery died pretty quickly with just the 4-ways going. But when I got it back from the shop it fired up better than ever. I thought maybe they had replaced something that was affecting it but they would have had to charge the battery to get it started again.

The last time my wife got stuck when it wouldn't start. She called me so I drove over (took about 20 mins + she in was in a store for about 10 mins). Once I got there she tried to start it and it fired right up. Just that 30 mins was enough for it to cool down enough to overcome the heat-soak I guess.

I also notice that my battery very rarely goes up to the 13.8-14V on the dash. Most of the time it's sitting down around 12.5. I'm wondering if it's just not getting the charge it needs from the car (maybe due to poor cables?)

The battery must be original. I've had this car since 2019 and was bought with only 1000 miles on it. And I've never replaced it....I'll take a look at it this weekend.

[indyz]

I have not done the ground wire thing yet on my 2016 SS.
I am in central FL, gets pretty hot here and I have experienced the slow cranks when I drive only short distances before shutting off the engine.

Recently I have started using a battery tender that has a "desulfator" feature. I leave it hooked up to the battery tender for a week at a time, each month.
I have not experienced any slow cranks since I started using the battery tender (in my garage) for 1 week, every month. Rest of the month, I just leave my car outside the garage.

My driving is predominantly 5 mile commutes, 5 miles to work, 5 miles back home. Kids.

EDIT: oh yes, I am on the original battery.

[chovaz]

Originally Posted by indyz

I have not done the ground wire thing yet on my 2016 SS.
I am in central FL, gets pretty hot here and I have experienced the slow cranks when I drive only short distances before shutting off the engine.

Recently I have started using a battery tender that has a "desulfator" feature. I leave it hooked up to the battery tender for a week at a time, each month.
I have not experienced any slow cranks since I started using the battery tender (in my garage) for 1 week, every month. Rest of the month, I just leave my car outside the garage.

My driving is predominantly 5 mile commutes, 5 miles to work, 5 miles back home. Kids.

EDIT: oh yes, I am on the original battery.

I'm also in central FL. I wonder if just hooking it up to the charger overnight once a week would do the trick. AGM require higher charging voltages and I've never seen my volt meter get over around 13.5-13.8 when driving. And most of the time it's down around 12.

[DamonZ28]

Originally Posted by SSDan

(extra ground cable gives that)

Sounds similar to the Big 3 Upgrade that the car stereo guys do. I did that on my 94 Z28 with 2 amplifiers and a stock-type battery. Never had issues with starting the car, or with headlights dimming or anything like that. Had it for several years, up until I traded up last November.

[indyz]

Originally Posted by chovaz

I'm also in central FL. I wonder if just hooking it up to the charger overnight once a week would do the trick. AGM require higher charging voltages and I've never seen my volt meter get over around 13.5-13.8 when driving. And most of the time it's down around 12.

Mine gets to 14v + a lot, whenever I do the short drives.
Did a long drive yesterday, where it started at 14+ and ended up around 12-13 after almost 45 min of driving.

I don't know much about the desulfation process, or if it's even effective, but some folks that work in the industry recommended that I leave my car hooked up to a battery tender with a "desulfator" for multiple days at a time.

Let's see what happens this summer, my battery is 7-8 years old. It probably needs to be replaced anyway.
Have not really had any slow cranks in the last several months, but at the first hint of trouble, I'll replace the battery.

[ChrisM]

Hi I had the same issue with my 2016 Camaro 2 SS. Been through 2 batteries and an 800 bill at the dealer to replace a cable(non-warranty). I did the ground update as mentioned STILL had an issue. I switched the battery from an AGM battery to a standard lead acid battery Same size same CCA and the problem has not come back. Hearing many bad things about AGM batteries....

[classicrockr]

After about a month of slow starts, my battery wouldn't start my 2016 RS today. Had it jumped & voltmeter was at 14 after 10 minutes of sitting & running. While driving, it went up to 15, then started dropping to just below 14 after a long traffic light. After stopping at a restaurant for dinner, it started & is staying right at about 14. I've got an interstate 48 month battery that's 2.5 years old - it shouldn't be going bad already. Yesterday my side warning systems started giving me "temporarily unavailable" messages too. Not sure if it's the battery or not.

[antyslope]

Originally Posted by SSDan

Like many I have dealt with a slow crank on a hot start pretty much since one year of ownership until now. So that is for about 3.5 years. 1.5 years ago the dealership replaced the battery under warranty for this issue. That kicked the can down the street for about a year. So, for the last 6 months I've been dealing once again with slow cranking on a hot engine.

I saw four paths to follow to attack this problem:
- add a new ground cable
- replace the starter
- replace the battery again
- sell the car

I decided last week to take the path of least resistance and add a new ground cable. So, I spent $40.00 to get one from Lethal Garage. I didn't have high hopes but miracles of miracles - it worked. I have driven the car about 8 times since adding the cable and I have not had anything even close to a slow crank on a hot engine. I have tried to make it happen by adding in short stops with each drive. Today I had four short stops and restarts in one trip. It cranked fine every time. Prior to adding the new ground cable I wouldn't have dared try that! Its the best $40.00 I have ever spent on this car.

If you too are dealing with this - I highly recommend you try adding a new ground cable.

Here is a cold start:
[https://youtu.be/n8Honktafms]


Here is the first hot start:
[https://youtu.be/Z_cqf_TfAm4]


Here is the second hot start:
[https://youtu.be/nyA-AfeJCmk]


I didn't add videos for the 3rd and 4th hot start as they were the same as the first two.

This video shows where I added the new ground cable:
[https://youtu.be/x1Q0s1vw9a8]


Edit: I just went back and listened this video and realized I failed to mention that the engine bolt I used is part of the serpentine belt system. I didn't take the bolt all the way out. I just loosened it and then cut a small piece out of the ear of the lug and slid the lug under the bolt and tightened it down. If you take the bolt out all the way you will lose tension on the belt.

Update 12/30/20: With the saying in mind that if one is good then two would be better - I added another ground. This time I took on the other end of the car and added another ground from the battery's negative post to the floor of the trunk. This cable is a little smaller (2.0 guage) and I bought it off of Amazon for $14.00. I placed the body end of the ground on a unused threaded stud sticking up out of the trunk floor (look to the lower far left in the photo). I have no idea if another ground is helpful and needed . I just added it for peace of mind - plus it was easy and cheap.

Please pay attention to the edit I added with the last video on cable location for the engine ground. Do not remove the belt tensioner bolt I used. If you do you will lose tension on the serpentine belt. Instead cut a small piece out of the cable's terminal lug making it look like a U and then slide it under the bolt. You can back that bolt out enough to slide the lug under it and tighten.

I continue to have normal starts whether the engine is cold or hot.

Attachment 1054234

When you put the extra ground for your battery, did you bolt the body end of the ground down to the unused body post, or did you just place it on there?

[SSDan]

Originally Posted by antyslope

When you put the extra ground for your battery, did you bolt the body end of the ground down to the unused body post, or did you just place it on there?

The photo doesn’t show it very well but it has a nut holding the cable on the stud.

[antyslope]

Originally Posted by SSDan

The photo doesn’t show it very well but it has a nut holding the cable on the stud.

Okay thank you! I did end up getting a ground for the battery. Sorry if I sound like a noob but I ended up ordering the Gen5DIY ground for the engine bay as well, it’ll be coming in a couple of days. I know you mentioned that you cut the ear of the lug to slide it under the tensioner bolt. I was just wondering what you used to cut it to make sure I have that tool ready for when it arrives.

Thanks again in advance

[SSDan]

That cable has a thick lug. If I remember right I put it in a vise and used a hacksaw with a metal cutting blade. You might want to skim through this thread and look for other engine connections that can be used. The other locations will not require cutting the lug. But if you go my way it has worked perfectly fine for over 2.5 years. Remember that if you make a lot of short trips (under 30 minutes) that the battery is probably not gettin fully charged. It takes a strong battery and a solid ground connection to overcome the slow crank every time. I now keep my battery on a trickle charger between drives since I only drive the car once or twice a week. Good luck.

[2SS Capt]

Originally Posted by antyslope

Okay thank you! I did end up getting a ground for the battery. Sorry if I sound like a noob but I ended up ordering the Gen5DIY ground for the engine bay as well, it’ll be coming in a couple of days. I know you mentioned that you cut the ear of the lug to slide it under the tensioner bolt. I was just wondering what you used to cut it to make sure I have that tool ready for when it arrives.

Thanks again in advance

Just as an FYI, here was my installation on my SS...

[chovaz]

Mine has got so bad over the last month that I never know if it's going to start when I get in it after going somewhere.....

Last time there was a strong electrical burning smell coming from the engine compartment.

But it still jump starts and runs just fine....

Thinking of replacing the battery (still original in 2017 Camaro) as a (new) starting point.

EDIT: new fun fact....trying to start just now (tried about 3x) something right under the engine caught on fire. Couldn't see exactly what but could see the smoke and glow. Luckily had lawn hose nearby to put it out. Guess it's dealer time (again)