'82 electrical problem while idle
Thread Starter
Instructor
Joined: Mar 2010
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'82 electrical problem while idle
Problem: Car almost sputtered out while sitting in traffic on my way to work.
Symptoms: Brake light on console stays lit. The door buzzer doesn't sound anymore.
Noticed the volt meter arm at start stays just about on the 13 mark (previously it would shoot to ~16 when turning the engine over), and while idling in D or R, any sort of high load device (lights for example) would help drain more power in a short amount of time.
There's no problem at high speed, just when I'm idling at a light.
What I've done thusfar and still no fix: replaced battery posts, cleaned terminals, cleaned the junction box, replaced the orange wire connector that connects to the junction box, replaced red wire that connects from positive terminal on batt to the junction box, and cut off the old ends from both battery cables (now shiny copper!). Also checked the E.brake switch, but setting it closed isn't turning the BRAKE light off on the console.
I haven't tackled the fusebox yet, but I'm going to do so now.
Symptoms: Brake light on console stays lit. The door buzzer doesn't sound anymore.
Noticed the volt meter arm at start stays just about on the 13 mark (previously it would shoot to ~16 when turning the engine over), and while idling in D or R, any sort of high load device (lights for example) would help drain more power in a short amount of time.
There's no problem at high speed, just when I'm idling at a light.
What I've done thusfar and still no fix: replaced battery posts, cleaned terminals, cleaned the junction box, replaced the orange wire connector that connects to the junction box, replaced red wire that connects from positive terminal on batt to the junction box, and cut off the old ends from both battery cables (now shiny copper!). Also checked the E.brake switch, but setting it closed isn't turning the BRAKE light off on the console.
I haven't tackled the fusebox yet, but I'm going to do so now.
Instructor
Joined: Oct 2008
Posts: 176
Likes: 1
sounds like a short with the car off remove the neg from battery put dc amp meter between battery neg terminal and negitive wire you removed. compare amp draw with what shop manual says it should be if its higher than spec start removing fuses one at a time to see which circuit is the problem then start tracing those wires use a wiring diagram book looking for shorts.
Thread Starter
Instructor
Joined: Mar 2010
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Was afraid of that.. Granted, I went through my fuses and all was OK in terms of continuity, and I pulled apart the center console because I thought it had something to do with the E.brake light switch (because the dash brake light stays on while engine on) and I actually found a cut brown wire. Fixed that with some solder, but idle drain still exists. Gonna pay someone else to look at/fix it probably. But thanks the same. 
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Was afraid of that.. Granted, I went through my fuses and all was OK in terms of continuity, and I pulled apart the center console because I thought it had something to do with the E.brake light switch (because the dash brake light stays on while engine on) and I actually found a cut brown wire. Fixed that with some solder, but idle drain still exists. Gonna pay someone else to look at/fix it probably. But thanks the same.
Once again that valve is one way. It could be electrical but I would check this first.
Jim
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
Jim [prior post] may have identified the problem for you. A leaky power brake booster will cause the car to run very lean at idle. This will give you very erratic idle condition and also drop idle speed so much that the alternator can't supply adequate charge to the battery (which may be why the brake indicator light was glowing). You can test that theory by removing/plugging the booster fitting on the carb, then letting the car idle [stopped] and put it in gear. If that eliminates the poor idle condition, the brake booster has a big vacuum leak and needs to be rebuilt or replaced.
Thread Starter
Instructor
Joined: Mar 2010
Posts: 105
Likes: 0
Jim [prior post] may have identified the problem for you. A leaky power brake booster will cause the car to run very lean at idle. This will give you very erratic idle condition and also drop idle speed so much that the alternator can't supply adequate charge to the battery (which may be why the brake indicator light was glowing). You can test that theory by removing/plugging the booster fitting on the carb, then letting the car idle [stopped] and put it in gear. If that eliminates the poor idle condition, the brake booster has a big vacuum leak and needs to be rebuilt or replaced.
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
He was right. The idle was so low with the booster connected to the carb that the power simply drained out if I turned the lights on or put the windows up/down. When I removed the hose, the idle was enough to keep that from happening. SO, I need to install a new PB (this one WAS new from one of the forum vendors). Thanks you guys for the diagnosis!
Good to hear.
Jim
