Chuck S

Battery voltage can drop to 10vDC and lower when starting, but otherwise should never see that high a load or low voltage Simple battery tester will show a weak battery even if it's seemingly at the right voltage not under high load.



-- Chuck

Car Analogy

Valve cover is already hard enough to pry off head. RTV ain't gonna make that any easier. Your next valave adjustment isn't going to start out fun.

You've done your grounds a big favor. Worthwhile effort even if it doesn't solve issue. I'm betting it makes a difference.

captb

So after cleaning the grounds seems like I am still getting inconsistent voltage.

At idle with all accessories off I am still getting 13.8V. With all accessories on (low beam, high beam, ac, heater, radio) it will drop to 12.4V and very slowly creep it's way up and settle at 13.4V.

If I rev to at least 2000rpm it will go directly to 13.4V with all the accessories on. With accessories off revving will bring it up to 14.0V.

With all the accessories on, at idle, and turning the wheel to engage EPS it will consistently drop to 11.8-11.9V then return to 12.4V when I let go of the wheel.

Not sure if this is normal behavior. under high demand it seems like it is relying on the battery.

I might just replace the battery for good measure. However, I'm wondering if that is just masking the problem. Not sure if it makes a difference but this is my weekend driver and there have been at least a handful of times that I've found the battery completely drained after not starting it for a few weeks.

captb

Fuses under dash and next to battery tested OK. Not sure what else to check.

captb

The more I think about it the battery is likely the issue. The voltage shouldn't drop below what the battery can supply, so it shouldn't drop below 12V.

windhund116

Maybe best to get the battery tested?

Car Analogy

Battery test only load tests the battery to see if its weak. If it has some sort of really odd issue, like an intermittent internal short, load test won't necessarily say its bad.

Battery went dead on several occasions according to recent revelation from op. Lead acid batteries hate that. If many of those also dead scenarios also involved fast charging, like jump start and recharge off alternator, batteries hate that even more.

Possible to temp swap in another battery, from any car with similar post terminals? Shame to spend ~$100 if that's not it. But with a history like that, and its age (its like 5+ yo iirc), might be smart just to replace it anyway. Ain't likely to have a long life ahead of it.

Chuck S

Starting batteries only survive a few dead battery episodes.

-- Chuck

twohoos

^Agree with the above. At 5 years your battery might not be "dead", but it's certainly past its prime.

flanders

Might be a bad battery but I wouldn't rule out the alternator either.
I haven't tested but it I think it should have no problems supplying all the accessories even at idle, not EPS though that is a very high current draw.
Check the positive connections from alternator and the fuse box.
You could also measure if there is any AC voltage with engine running, that would indicate alternator problems.