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EFI Ignition problem. Please HELP!!!

68EFIvert

68EFIvert

Well-Known Member
I have been having problems with the batteries in my car lately. I replaced a 6/7 year old Optima battery 2 months ago with a new red top optima. That battery was dead after the car sat in the month for 2 months and I did not even drive it. I thought it was just the new Mexican made Optimas. The auto parts store tried to talk me out of getting it becasue they have been having problems with them. Fast forward to Saturday when i exhcange the new Optima for an Orbital battery.

I did not have time to drive the car on Saturday so Sunday was going to be the day. I pulled the car out of the garage and it ran like crap. Sputtering, smoked like hell and the engine light came on. WTF. I drove it from a house we were moving it from last week after I jumped the 2nd optima battery. It ran fine. Now I change the battery and it runs like crap?

My code reader is burried in a box until the new house is built so I go the the parts store and buy another reader tonight. Go to turn on the car and the battery is dead. I am now thinking that my problem is much deeper than my battery. I plug in my charger and hear some clicks in the engine compartment. Since my battery is located in the trunk I asked my wife to come out and plug the charger in while I look for a short or something.

When she plugged it back it the coil was making some clicking sounds and I could see some sparks inside of it. The distributor cap seemed to be clicking as well. Could a bad MSD coil cause these problems? I assume when the MSD box goes out there would not be any spark. The rest of the ignition system is and MSD BTM box, MSD 6AL box, MSD distrutor, MSD TFI coil and new alternator. The oldest part of the system is the coil, MSD 6AL and BTM boxes. They have about 2000 miles on them. Thanks for the help!!!!

Needless to say I did not hook up the code reader since the car doesn't have enough juice to turn the lights on.
 
Was the key on or off when the clicking was going on?

The 6AL is supposed to be powered by a key on source as I remember.
 
Reading MSD instructions now.....

Found this tidbit.

Initial Spark: It is normal, yet not very common, for the MSD to produce a spark when the ignition
key is turned On. This is due to the capacitor being charged and if the pickup is in the right position,
it could trigger the ignition momentarily. This could also occur when installing the positive battery
cable
 
Regarding the batteries, have you gone through the process of removing the fuses one at a time and measuring draw on the battery to determine if you have a slow drain from something?
 
Two power leads and a heavy red go straight to the battery.

Heavy red carries this note.
Note: Never connect the alternator

I did not look for an internal diagram of the box but I'm gonna guess the two power leads go to the capacitors inside the box. If the capacitors have shorted to ground I'm sure they could drain the battery in a hurry.

Try disconnecting the two power leads and see if the battery dies with them disconnected. if it still dies disconnect the heavy red and see if that fixes it. If not reconnect those wires and disconnect the switched wire from the ignition. If that fixes it, I'd look at the possibility that the ignition switch is not turning off properly.

Of course you'll have to charge the battery between checks if it's dead.
 
BTW, Rick had a similar problem recently and last I heard the alternator was the problem. He was running a 1 wire IIRC.
 
Thanks for the help guys. I am charging the battery with it disconnected. I have already unplugged the two small red wires. Once the battery is charged and holding the charge I will connect it to the car. If it starts draining right away I will know that may be the problem. If it holds it I will disconnect the large red wire like you suggested.

I haven't had a chace to check for other draws. Quite honestly I wasn't sure where to begin. Electricl stuff is like the great unknown for me. I am much better than I used to be but not confident at all when it comes to electrical problems.

My battery was just put on the car this winter. That doesn't mean much I guess. it is a Tuff Stuff chrome alternator that puts out 150 or 200 amps IIRC. Thanks for the help in giving me a direction to look for the problem.
 
I charged the battery and it holds a charge when disconnected. I unplugged the 2 small wires on the MSD box then connected the battery. The battery dropped rapidly. The large red wire is much harder to reach. I have to pull the blower inlet and MAF meter to reach it. Good project for tomorrow night.
 
The switch idea may make sense. I took apart the dash for paint over the winter and started having the problems after that. I know it turns off to a certain point because the fuel pump primes when I turn the key on.

I thought about replacing it but decided to save the time of ordering one. I may need to go back and do it later.
 
Progress report. I started pulling fuses before taking apart the MSD box any further. I found that when I pulled the fuse that runs the courtesy lights the drain on the battery stops. This makes sense since this winter I repainted the dash and fixed what I thought was a short in my passenger side courtesy light. A PO had twisted loose wires together to operate the light. I reconnected it using connectors and put a new fuse in. The lights seemed to operate just fine. Is it possible to connect the lights the wrong way? + on - and - on +?

What other items work off the courtesy light fuse. My wiring book is packed away in a box. Thanks guys!
 
On a 68, the following items work off of the courtesy light fuses: courtesy lights, glove box light, map lights, clock light.
 
If you have a clock it will obviously cause a little bit of battery drain (assuming it works!), but how much of a drain this I do not know.
 
So if I live without interior light the car will run correctly. What would cause the battery to loose 1 volt in a priod of 15 sceonds. Could a short do that? Wouldn't the fuse blow before it would do that? Sorry for all the questions.
 
You mentioned that you had to fix a connection for the pass. side courtesy light. You may want to pull the door switches and make sure one of the connections isn't touching the metal where they go thru the door frame area. Just another thought of a possible shorting area for that circuit.
 
"68EFIvert" said:
So if I live without interior light the car will run correctly. What would cause the battery to loose 1 volt in a priod of 15 sceonds. Could a short do that? Wouldn't the fuse blow before it would do that? Sorry for all the questions.
Click to expand...
The system is fused with a 20Amp fuse (presuming it is the correct fuse). A short would cause the fuse the blow. A severe battery draw-down indicates a weak battery as well.
 
The battery drain is there when the door is open or closed. It doesn't seem to matter. Does the ignition switch have anything to do with that circuit? How about the headlight switch? IIRC if you turn the headlight switch you can turn on the interior lights. :shrug
 
Nothing to do with the ign. switch. The headlight switch ...... you are correct. There is a small lobe felt as you turn the knob. It also controls the brightness of the dash lights.

Do the interior lights shut off when the door is closed?
 
The lights do turn off. The other thing I was thinking about is the horn. I am using a GM wiring harness and Flaming River column. Since the horn is a constant hot item like the courtesy lights I wonder if it could be on the same circuit. I had the steering wheel off this winter for repaint and wonder if the wiring could be the issue there.

I was speaking to a buddy today about this and he suggested hooking up the charger to the car and feeling for a warm wire. Once I found the warm wire he was convinced I would find a parasitic ground that is not enough to pop a 20 amp fuse but could draw down the battery pretty quickly.
 
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