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I was a moderator on thecorvettemechanic.com for a few years, so yeah I definitely know who Paul is.
Yeah kinda hard to argue against anything he says. While there seems to be a pretty hard line around here of AGM is bad for C7 versus no it’s totally fine…Paul’s words are pretty much gospel to me. With the trophy case I have, it’s easy to be a super arrogant technician and come up with my own diagnosis and die on that hill. But I think I’m gonna yank out the Optima and just use it as a shop jumper (an expensive online at that) battery or something. Guess I’ll get a new flooded in there when I replace the negative cable.
When I purchased my 08 that had a Yellow Top that was less than 6 months old I yanked it out and installed an AC Delco Professional.
I've had an Optima yellow top in my Z06 for 2 years. Sometimes I put a maintainer on it, sometimes I don't. Hasn't been a problem yet. I put a AGM in my 11 GS and it did well to. But I will say that since their last buyout quality isn't as near good as it used to be. I've heard of many bad ones out there.
He’s working for GM now and he’s a sharp tech but I don’t know how he is as a diagnostician…2 different skill sets entirely…I think he was involved in some lawsuit on his website so don’t know what happened there but I believe its inactive now.
That forum has been inactive for at least a few years now. To be honest, there wasn’t much activity there a few years before that.
He’s as good as they get when it comes to how systems actually work. That alone is half the battle when it comes to diagnostics. How he is when it comes specifically to electrical diag, which is an Achilles heel to many technicians (mine apparently is evaporative emissions…I always seem to get burned on those), I would like to think he’s an ace but don’t know for sure.
Electrical and the Labscope is my favorite and the GM EVAP system is about as simple as it gets…Toyota is very complicated…there are many great YouTube videos on EVAP…Go Tech is a good channel…just takes self study.
Optima? Well marketed but overrated.
Odyssey? Good stuff.
I put an Odyssey in 1878 right after I bought it. Five plus years and counting. Starts with lots of umph. I took it on the '24 Caravan for which I worked as a Caravan leader. It survived all my radio gear left on during fuel and food stops.
Just an update on this little saga in case anyone cares. Got a bit sidetracked since four weeks ago some POS thug smashed the drivers window when I was parked at a mall for 90 minutes. Cameras everywhere and tons of holiday shopping traffic…they got some calls I’ll give them that. So now that I’ve replaced the window (quite a bit easier than I was expecting actually) today I got around to fixing my electrical issue…
Kinda nice being able to lean right through the halo hood sometimes.
Originally Posted by NicD
It's your alternator and the voltage spiking over 15V, I promise. Replace the alternator, it's easy and cheap.
Originally Posted by Thomasmoto
I'm on my 3rd alt in my 16 Z06 and my 2nd in my 19 ZR1. Both cars in their 70K's miles wise. They overcharge and it sends the car into fits. If it's going over 15 volts it's a pretty good guess that's what it is. JMHO
So yeah. It was the alternator. Before the incident with the broken window, I’d been watching the voltmeter in the gauge cluster. Saw it getting in the high 15s, then 16, and then as high as 16.6 volts. So ok that sold me, that’s beyond its operating range. Even for the slightly higher than normal range the C7 uses. Oscillating brightness (or flickering) of exterior lights is a super common symptom of a bad alternator. Since the charging system of the C7 can be at 15.5v and that can be a normal condition, I didn’t immediately suspect the alternator was overcharging.
Good to see the OP replaced the AC generator and solved the problem.
There was some discussion about adsorbent glass mat (AGM) batteries in this thread.
As far as I know, the OE battery in a '19 ZR1 was an AGM battery. That the ACD catalog recommends a H6/Grp 48 AGM battery seems to indicate there is no problem using them in a C7 ZR1.
There has to be someone here who might have an original battery in their car. I know it's a PIA to get at the battery but it would be interesting to see whether or not AGM was OE on ZR1 for MY19
Good to see the OP replaced the AC generator and solved the problem.
There was some discussion about adsorbent glass mat (AGM) batteries in this thread.
As far as I know, the OE battery in a '19 ZR1 was an AGM battery. That the ACD catalog recommends a H6/Grp 48 AGM battery seems to indicate there is no problem using them in a C7 ZR1.
There has to be someone here who might have an original battery in their car. I know it's a PIA to get at the battery but it would be interesting to see whether or not AGM was OE on ZR1 for MY19
Even though I replaced it over a month ago, my shop still has my original sitting around (our vendor doesn’t come to collect them all that often).
While there is nothing labeled on here defining whether it’s AGM or flooded, a quick shake to hear the acid sloshing around very much confirms this is a flooded battery. Looking though a list of AC Delco batteries, it seems the “PS” in the 48PS is how you know. Seems like all the flooded batteries have the group number with PS or PG after it. And an AGM would be a “48AGM” label.
Good to see the OP replaced the AC generator and solved the problem.
There was some discussion about adsorbent glass mat (AGM) batteries in this thread.
As far as I know, the OE battery in a '19 ZR1 was an AGM battery. That the ACD catalog recommends a H6/Grp 48 AGM battery seems to indicate there is no problem using them in a C7 ZR1.
There has to be someone here who might have an original battery in their car. I know it's a PIA to get at the battery but it would be interesting to see whether or not AGM was OE on ZR1 for MY19
Hey Hib I am the original owner of my 2019 ZR1 (purchased July 2019) and it still has the OEM battery, its a AC Delco Grp 48PS, 615CCA and 110RC Flooded non-AGM battery. I was going to replace it with a Interstate Flooded battery but changed my mind and decided to stick with flooded AC Delco battery . I just checked the surface charge and did a loaded test and all is good but I will replace it at the start of summer. Yes when not being driven l keep it plugged in with the OEM battery maintainer.
My 2019 Cadillac CT6-V came with a original AC Delco Grp 49 AGM battery, 900CCA and 160RC (non- flooded) and that to is stil going strong !
So far very good luck with AC Delco !
