Hello fellow 3rd gen...Long time problem...never solved...battery dies when it sits. Wont charge...new battery, starter, cables, alt...

One clue...problem started when the starter shorted out by the positive battery cable "grounding" to burned AIR pipe...

At my wits end...ALL assistance appreciated!

I gave this car away...and it came back...they kid (daughters boyfriend) got fed up with it too...

83 z28/305 -5speed


HELP me...or this is gonna end bad...

Jim

 

Hello Jim,

Before you throw it away again, check your e-mail.

 

Let's take a shot at this from another angle...

Step 1- Positive battery cable shorted out on hot AIR line...

Step 2- Car died but restarted (after moving welded battery cable off AIR)

Step 3- Replaced Starter, alt, battery and cables

Still wont run more than a few minutes, and the battery drains down when it sits...

What is the next step of replacement...Ignition module, coil, ECM...??javascript:smilie('')
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All help appreciated!

Jim

 

Does the "Choke" light come on when the key is turned to On but the engine is not running?

 

Not that I noticed...but I will check tonight...what does this indicate?

Thanks for all the help! If it was NOT for all the people on this site, I would have dumped this car in the river a LONG time ago...

Jim

 

OK...with the key on but the car not running, the CHOKE light does come on...

I put the multimeter inline between the negative cable and the terminal. Getting a reading of 7.5 ma...pulled all the fuses one at a time, and the only one that had any effect was the radio/clock. When I pulled that one, it dropped to 3.0 ma...nothing else changed.

I am thinking of swapping out the IM tomorrow night as I have an extra...

Any other advice?

Jim

 

The choke light is really the bad alternator light. Its not wanting to take a charge.

I dont know, i guess i just like asking this? Do sparks go everywhere when you disconnect the negative battery cable and tap it to the post?

*just thinking aobut this, this a very random thought, lol. But i do know that if the alternator is bad, the choke wont get its 12v source to heat up properly so it wont shut off after a few minutes. Perhaps, is what is happening is you start your car, choke does its job and shuts off the air supply, creating a rich environment while the car warms up. NORMALLY, the choke warms up due to it receiving a 12v source and then it eases off and opens up to let air in. PERHAPS, is what is happening is your alternator is bad, so the choke is getting a charge, so when you start your car, the choke closes, but since theres no 12v source to the choke, theres not heat to tell it to open. That in turn eventually suffocates your motor and it dies. i have NO clue if that is even possible. Its late and im tired. that is one of my crazy late-night thoughts.

**then again, your car might not even be carbureted.

 

Alternator is NEW...plus I tried it with three others that I know are good from other "projects"

Could the choke have shorted out? Would that cause the same condition...

Can I manually operate the choke...It is running rich...sure smells it...That would explain a few things...Not the charging. but a few things...

Jim

 

OK, so the "Choke" light bulb is good. A bad bulb will prevent the alt from charging, because that little bit of current through the bulb is how the alt "knows" that the ignition is on, and that it's time to charge.

Continuing on....

Does the "Choke" light go out when the car is running? What is the voltage as measured across the battery terminals with a digital multimeter when the car is running?

 

RB...thanks for the update...I have been reading old posts on the search, and you seem to BE the man in this area...

The CHOKE light goes out when the car starts...I will check the voltage across the terminals tonight...

Several older posts mention a bad battery cable...When the short on the AIR pipe happened, I KNOW that i only replaced the POSITIVE cable...

Could ALL of this be a simple bad ground? I can't seem to think so...my knowledge of electrics is NOWHERE near yours, but that doesn't make sense unless something has 'jumped". Could a ground strap missing on the head after installtion give it fits?

I love this car, but it is NOT fun right now...It would be worse if the weather was warm and sunny...

Thanks Again!

Jim

 

OK...I checked the voltage across the battery.

12.75 Car off
12.05 Key on
15.05 car running.

Next step...?

Getting there is NOT fun...most of the time...


Checked all the ground straps, and all are in place, and don't appear damaged or corroded....?

Jim

 

After the car has not been running for a while (two hours) put your hand on the alt. and see if it is warm

you said:
what do you mean it wont run for more than a few minutes

 

I can keep it running while sitting in the driveway, but it requires attention. If not, the RPM's slowly drop, until it just dies. The RPM drop seems to be power related...like it is struggling to get power...when this starts to happen 60 sec after start up, the car bogs when you give it gas...it does pick up , but almost a flat spot off idle...lack of juice, air, gas?...

I think one of the plugs is fouling up too...this sometimes acts like a bad carb, but I don't think it has enough spark due to power loss to burn all the fuel...

Keep 'um coming!
ALL help appreciated!!!!!!!!!

...Plus as an added bonus, if I can't get this solved, the person that posts the most helpful suggestion will get the car for FREE...;-)...

Jim

 

When was the last time you fully charged the battery? The reason I ask this is to do thorough troubleshooting you have to start with a fully charged batt. Also on the amperage draw you say 7.5 Ma just checking that that was on the milli amp scale on the amp scale that would have been .0075

 

The battery was fully charged when I tested it...charged at 4 amps for 12 hours...

The 7.5 ma I will have to check on...you are right...if that read 75 ma...then I still haven't found the problem. It did drop to 3.0 (30 poss)..when I pulled the fuse on the radio...one thing I noticed this moring when I opened the doors...no interior lights...Now I know the dome light is burned out, but I thought the interior lights (underdash) were working...

Thanks...

Jim

 

Jim,

Just for s**t's & Grins, check the purple wire that goes to the small terminal on the starter solenoid marked "S". This wire goes to the P/N switch on an automatic and the clutch start switch on a manual. and might be shorting out and causing the drain and preventing the battery from charging. It's just a thought but heck, almost everything else has been checked. While down there you might as well check all your fusible links as well.