[Choda]

noticed something last night. I already have a ground from the neg body post to the side of the block. Did you guys already have that ground and then added a second to the water pump?

[TP2SS]

Originally Posted by Choda

noticed something last night. I already have a ground from the neg body post to the side of the block. Did you guys already have that ground and then added a second to the water pump?

I've been wondering where that cable on the post went to. Now I'm wondering if the issue is a bad/dirty/corroded connection at the block, and the extra cable we've been talking about is unnecessary. Although that existing cable does seem to be undersized. Maybe the real solution here is to replace it with a 1/0 or 2/0 AWG cable and forget messing with the second cable?

[oldguy0130]

Originally Posted by Choda

noticed something last night. I already have a ground from the neg body post to the side of the block. Did you guys already have that ground and then added a second to the water pump?

or possibly loose from the factory?

[SSDan]

Originally Posted by Choda

Did you guys already have that ground and then added a second to the water pump?

Yes

Originally Posted by TP2SS

I've been wondering where that cable on the post went to. Now I'm wondering if the issue is a bad/dirty/corroded connection at the block, and the extra cable we've been talking about is unnecessary. Although that existing cable does seem to be undersized. Maybe the real solution here is to replace it with a 1/0 or 2/0 AWG cable and forget messing with the second cable?

By adding the second ground cable and then having hot starting success that told me that there was indeed a bad/corroded/dirty/loose and/or undersized factory ground.

I'm operating from the thought process that adding additional ground(s) can never hurt - it can only help. I have no interest in crawling around under the car to chase a factory ground that isn't getting the job done. I don't have access to a lift and I am no longer comfortable crawling around under cars on jack stands unless its absolutely necessary.

All I ever wanted was a car that would start like every other car on the road once the engine was fully warmed up. Adding this second ground cable accomplished that - mission complete!

Please post back if any of you find the factory ground has one of these issues (corroded, loose -etc.) and once fixed it resolved the hot start issue. That way forum members have multiple ways to attack this annoying issue - which by the way seems to be mostly with the 2016 SS models.

Also, some have posted concerns about voltage readings since they are seeing 14v+ readings while driving and then concerned about overcharging. So, today after a 40 minute drive with three stops (and perfect re-starts BTW) and seeing 14v on the gauge much of the drive - I measured voltage at the under hood contacts with the engine off. It read 12.56v which is just about right on to a fully charged battery reading of 12.6v. No overcharging is evident.

I want to thank all those who have contributed with thoughts, photos, parts sourcing and additional solutions!

[fxdxron1]

When I brought my car to the dealer for this problem a couple of years ago and they said they checked all the ground connections and the problem still existed so maybe it's just a undersized ground wire.

[MackSteelPrivateEye]

Originally Posted by RA1987

Yes, that is correct. No issues so far but I planning to move it once I get the right bolt.

Why did you connect it there even temporarily? Body to body is not grounding anything.

[MackSteelPrivateEye]

Originally Posted by GroundhogSS

I hooked the extra ground up via the water pump bolt on Saturday. Every time I've driven it since them, it spends most of the time with the volt meter above 14. I verified it with a volt meter at the posts under the hood and it was 14.4. I hope it doesn't fry my battery. I think I may try the second cable in the trunk.


SSDan, do you have a link for that trunk cable? Thanks.

I would think as long as you have a good working Voltage regulator it would limit the amount of voltage to flow within the safety margins specified. Thats what its there for to regulate voltage.

[MackSteelPrivateEye]

Originally Posted by GroundhogSS

OK, after three days of short trips where I saw the 14+ volts almost continuously, I went out today and it was reading about 12.5 to 13 most of the time. It would occasionally go over 14 and then right back down. I added an extra 10 mile loop to the trip to give it time to stabilize. I guess (hope) the battery and the system is adjusting to the better ground. Going to add the extra wire in the trunk anyway. Thanks for all the help.

Our charging sys is computer monitored and it adjusts itself as it sees fit as required by the load. Thats why it fluctuates unlike the older cars that stay at one voltage output at idle. Although you would see a slight increase in voltage as you gave it more gas.

[RA1987]

Originally Posted by MackSteelPrivateEye

Why did you connect it there even temporarily? Body to body is not grounding anything.

Experiment. Understood. Ground or no ground the issue is now gone.
Would there be any long term issue with my current set up?

[TP2SS]

Originally Posted by MackSteelPrivateEye

Our charging sys is computer monitored and it adjusts itself as it sees fit as required by the load. Thats why it fluctuates unlike the older cars that stay at one voltage output at idle. Although you would see a slight increase in voltage as you gave it more gas.

This is correct. IDK about the Camaro specifically, but I am well-versed in 12V systems in boats as mine has a complex 12V system with massive AGM batteries. AGMs are finicky and like to be charged at certain rates. Their life can and will be shortened by improper charge profiles.

AGMs require 14.1-14.4v for absorption stage and 13.44-13.56v for float stage. This is likely why someone here was seeing 14+ on short trips and in the 13's after driving awhile. I don't think we should ever be seeing in the 12's while our cars are running, but some here report that and some have said that's normal. IDK what the Chevy engineers have done or how it's supposed to work, but on my marine application I never see less than 13.5 while the shore power charger or engine alternator are running.

[Mike Aruba]

Just wanted to provide an update to this thread.



I did this last week (1/27/21), in hopes that it would help with the RPM gauge fluctuating randomly, and so far I haven't had it happen once. It did it practically every time I drove the car before. Will check back in if it begins doing it again, but fingers crossed this finally fixed it. Thanks Dan!

[sanzieu]

Originally Posted by CamaroJim56

So, just got a 2016 2SS, what happens when they get hot and you try to start?


Thanks,
Jim

I bought a 2016 2SS in 2019 which had 44k mileage. I've had to replace my battery when it wouldn't start and later I also replaced the starter. The starter replacement took several hours to remove and almost as much time to re-install. If you can afford it, take it to a garage and have them do the work with the car up on a lift.

[ctrlz]

Originally Posted by TP2SS

I've been wondering where that cable on the post went to. Now I'm wondering if the issue is a bad/dirty/corroded connection at the block, and the extra cable we've been talking about is unnecessary. Although that existing cable does seem to be undersized. Maybe the real solution here is to replace it with a 1/0 or 2/0 AWG cable and forget messing with the second cable?

You can measure resistance between the neg terminal post and the block. Should be 5 ohms or less, with 0 being optimal.
Alternatively you can pull the fuel pump fuse (F35, rear compartment fuse block on trunk floor) and measure voltage across the same points while someone cranks the starter. Should be 0.2 V or less.
The heavy gauge wire you are suggesting sounds like overkill to me for a starter circuit.

[nystyle246]

GOOD INFO... MY SOUND TUBE IS LONG GONE. CAN ANYONE TELL ME WHAT THAT BOLT SIZE IS???