Guro 305

Does anyone else have this problem? If I let my car sit for a week without starting her up, the battery will not have enough juice to turn over.

My friend who also had an '86 Camaro used to say the samething. I'm starting to wonder if this is the way it is with these older cars. Do they really need constant starting even when not going to be driven or is my problem something deeper then that? The battery is new. The alternator was tested.....good! I just installed brand new battery terminal cables but it used to do this even before then.

Is this just the way it is?!

Ward

iTrader: (1)

Something is likely drawing current while the car is off. One thing I can think of would be the power hatch pulldown motor - it should emit a fairly loud click once it's pull the hatch down tight. That's the sound of the reversing switch in it cutting power to the motor. If the latch assembly is adjusted down too far, the switch will never flip, and the motor will try to run full time.

I would also recommend getting a multi-meter and measuring current draw across all of the fuses with the car off. Nothing except the radio and ECM should be drawing any current, and even those will be very small amounts of current.

evans87

I too am having a problem with a draw on my 87 convertible. I am new to the electrical game and am wondering how does one measure the current draw across all of the fuses? I did remove the negative battery cable and hooked up a test light between it and the negative termainal. I removed the hood light and ensured the door light switch was pushed in. The test light lit brightly. I pulled the fuses from the fuse block one by one but could not get the test light to go out! Now what should I do?

Ward

iTrader: (1)

You need a multi-meter to measure current draw. You can pick one up at Radioshack/Fry's for $10 to $20, and it's an invaluable tool for testing circuits. You will need to get one that allows measuring a decent amount of current though, some of the cheap ones don't. This is the one I bought, I got it for $10 at Fry's:

http://www.sourcingmap.com/black-dig...b-p-18160.html

It's hard to see in the picture, but there is a third plug above where the red lead is normally plugged in, labeled "10A". To test current draw, you plug the red lead in here, and let the circuit draw current through the meter. The 10A means that it can handle up to 10 amps (different meters will vary), which is fine for pretty much anything on the car except maybe the fans.

To test draw of a particular circuit, you first set the meter in current mode by connecting the red lead to the 10A plug, and turning the dial to point to it. Then, remove the fuse for the circuit, and touch each meter lead to one side of the fuseholder. If anything is drawing current on that circuit, it will go through the meter, and you'll be able to see how many amps it's drawing.

evans87

That is an easy to understand instruction, thank you! Just two questions, where do I plug the black test probe in? What reading would indicate a problem? Thanks again

Ward

iTrader: (1)

Black test probe goes in the bottom plug, COM (common, ground), and the red goes in the top 10A one. I wouldn't expect anything to be drawing anything more than a few hundred milliamps at most (the reading will be in amps, so 0.5 means 500mA). The ECM and radio both use a tiny amount of power to keep things in memory, like error codes and radio presets. Other than that, nothing else that I can think of should be drawing any current.

I'm not sure what the amp/hour rating on a car battery would be, but it basically works like this: If you have a battery that's rated for 1 amp/hour, that means you can draw 1A for 1 hour, 2A for 1/2 hour, 500mA for 2 hours, etc. It's not quite that perfect, since all batteries self-discharge somewhat, and there is also energy lost to heat, etc.

Guro 305

So pretty much only the ECM and Radio should draw any amperage with the car off is what I think you gents are getting at. Anything else would most likely be the cause of the problem.

Guro 305

This was a guess but so far it appears to be the issue. I disconnected the alarm the other day because for whatever reason I could not shut it off with the remote.

I forgot all about it and let my car sit for six days this time. I was certain I was going to have to charge my battery as six days is way too much time to let the car sit without having started it. Oh well, I said what the heck I'll give it a try. Started right up with a glitch and has done so ever since. I've driven her all weekend and it's been fine. It looks it it was the alarm after all. It's not that big a deal considering the only thing the alarm did anyway was make noise and nothing more but I'll most likely be shopping for a new alarm system.