forg0tmypen

First question:

When I start the Z06 first thing in the morning, it fires right up no problems. When I go to start it again, it is a lot weaker. It struggles to fire up the car. Wondering what the forums thoughs on this were?

Second question:

When I start the car repeatedly, it fires up but very very weak. Ive had two different starters on the car, same results so I went back to the original factory one. I also tried to unhook any wiring mods I did like "mild to wild" switch etc and no difference. Also replaced the battery and that made a difference in terms of being able to start the car whenever I needed, old battery would give me 3 starts then would fail to fire the car. Wondering if this is just normal for this car, I cant remember what it used to sound like years ago when starting over and over.

Third question:

When the car fires up and all the needles in the gauges rotate 180 degrees, the battery voltage settles on 11.5ish volts before the alternator charges it up to 14ish volts. I've seen videos on yt where their needles settled on 13+ volts upon start up. Is this a battery specific thing or should my battery which is an autocraft gold model from advance auto parts (the 600 cca model) be holding 13volts upon startup?

Fourth question:

How can I check if I have a drain on the battery?

Here's a video of a 2010 stock z06 model being started up on you tube. Pay close attention to the battery needle. It goes to 13, then immediately to 14.5 volts. Mine goes to 11-12 volts then slowly moves to 14ish.


Here is a cold start up of my car for comparison:


And here is a few seconds later, me starting the car again two times. Watch the battery needle.

forg0tmypen

ttt

jymboslice

How old is your battery?

forg0tmypen

its a new battery. Read first post

JWingo

It appears with each start, the battery is requiring a longer amount of time for recovery of charge. If you have a DVM, (Digital voltage meter), check the current at the alternator charge lug on back of the alternator itself. Compare that to the amount reaching the battery. Should be within 1 VDC or less. Check the connections on the alternator and the starter solenoid connection. A Parasitic drain would have more of an effect after the car sits overnight. This sounds like typical low voltage. Check the connections, compare the voltage.

harrydirty

I think you mean check the "voltage" at the back of the alternator charge lug................basically, this is good advice, checking for resistance at connections which could drop your voltage by the time it gets to the starter. Parasitic drains are not much more difficult to detect, but it requires disconnecting something so an ammeter can be inserted into the loop.

Good luck with the diagnosis.

forg0tmypen

This sounds about right. Battery is having a hard time recovering between starts. Replacing the battery has been slightly helpful, however is has only gotten me so far. Why is the battery having a hard time reocvering between starts? Think it's just a bad battery or is the alternator going?

Gary '09 C6

^ that certainly s/b investigated, sounds logical...

also re-check the end of the positive battery cable where it connects to the starter...there have been threads discussing damaged/burned starter posts and/or wires. You did say you replaced the starter, but maybe you overlooked this ?

(also assume the cone-shaped nuts on the battery cable clamps are tight)

IMO a fully-charged battery s/b showing at least 12.5 volts (or higher) right after start-up..

Dirty Howie

Is part of your problem, that when you restart, the motor is warmed up and has more compression as everything has expanded. My car is always harder to start when hot with original starter and second battery, 144K miles.


DH

forg0tmypen

Tightened down both nuts and I didn't replace the starter myself but had a local lsx shop do it 3 times. I mentioned the starter solonoid to them and the checked all the grounds and all the wires of the car as well to no avail.

JWingo

Yes Sir. That would be what I'm referring to.

JWingo

The Corvette will have a certain amount of drain present due to modules which need memory retention. Parasitic drain can be tested however. This is to say, if you have a inductive amp meter, clamp it around a battery cable. If you detect what would be excessive, pull one fuse at a time until the drain diminishes. I know when we certified, a 60 milliamp drain was considered acceptable for an 8 hour period. If you don't have an inductive clamp or meter, using a Digital Meter, you can remove a cable from the battery. Basically put the meter inline on the fused circuit and it will show the amount of current flowing.

SonnyAK

Just curious if you regularly keep your car on a battery tender?

NORTY

Louis, you're almost out of gas!

Your voltmeter is acting typical.

Do you know how to check what your static voltage is?

The best way to "test" a battery is under load.

forg0tmypen

Well no. I drive it every 3 days or so.

forg0tmypen

I'm very inexperienced with batteries and voltmeters and reading them. So I really don't know where to start.

SonnyAK

Sounds like you drive it regularly enough for that not to be the issue...
Good luck in figuring it out...Stuff like this can be a real pain sometimes!

Carnac

Even new batteries can fail. I had a new battery in my C4 die three weeks after purchase. May be something draining your battery, but from your indications, it would seem to be a marginal battery cell.

Jim

capevettes

I have had this happen. Some of these batteries sit on the shelf for long periods of time and you are essentially buying an old battery.

Without a battery tender on the car during periods of inactivity the battery will always be in a depleted state because of the systems it needs to maintain. Your alternator will be working to charge the depleted battery when you start it and drive it. If you drive it every 3 days but only short trip it, the battery will never reach a full state of charge.

If it were my car, I would buy a quality new battery like an AC/Delco Professional series from a shop that moves batteries and doesn't allow them to sit on the shelf for long periods before sold.

I would also get a good battery tender like a C-Tek 3300 and hook it up whenever the car is going to sit.

DON T.

After my first battery lasted 7 years in my Toyota FJ cruiser, the second one lasted 4 months! Tech said these batterys can sit for a year in some cases. Ofcourse turning over a six cylinder VRS an LS7 are very diff indeed.