Random electrical issues

[FordPrefect]

A little while back, I replaced my timing belt, took her for a test drive, and everything seemed great. The next day, the car wouldn't start.

It would fire up, but not continue to run, like it was an idling problem, but giving it more gas didn't help. The tachy went a little nuts seconds before this happened as well. So I got some wiring diagrams, pulled the alternator, etc. Everything seemed to check out, put the alt back, cleaned the contacts on some relays, and boom, car starts and works ok. Battery was replaced just a few months ago, it's fully charged.

However, I noticed that each subsequent start was a bit more sluggish than the previous, the dashboard lights are extremely dim when the headlights are on, but with the switch in the middle position so only the dash is on but no headlights, the dash is crazy bright. When I put the key in and turn it to the first position MAR(? can't remember right now) the charging light on the dash doesn't go on, nothing goes on. Yesterday the battery was too low to crank, but seems fine after charging it for an hour or two. Also, after years of not starting on the first turn of the key, it started perfectly the first try right after topping the battery off.

Anyway, my plans are to remove and clean the connections on my grounding cable and drop the dash down and figure out how to test the charging light. I have an older alt which uses the regulator on the driver's sidewall, and don't really know how to test the regulator really. I figure I'll have to spend some more time checking the gazillion wires and connections with one of the diagrams I've downloaded.

So, more gremlins to track down? What's a good way to check the charging light in the dash? What would make my headlights dim the dash so much?

[TX82FIAT]

Sounds like you are off to a good start. A newer battery not holding a charge would lead me to think of a grounding issue or as you have pointed out the voltage regulator. You mentioned the charging light does not come on with the key in the first position, it should. You should be able to hook a voltage meter up after the voltage regulator and see what is coming out as well as hook one up by the battery. I'm not real familiar with the seperate voltage regulator. The instrament panel is set up so you can pull the bulb if you have small hands from behind the dash. A new bulb or plugging a bulb you know owrks in is cheap and quick. The headlights are know to dim over time as the grounding becomes less effective.

Check grounding pods, check large ground cable near transmission. What year is your car? Read up on Brown wire fix as well as headlight relay fix. The electrical gremlins can take some time to get sorted out. Again, sounds like your on the right track. battery or alternator or voltage regulator or grounds. I would not think it is ignition related based on info provided.

[FordPrefect]

It's supposedly a 77, but I'm starting to think it's a 76. My main ground cable is bolted to the transmission, but looks like it is clamped into a welded bracket of some sort onto the frame, I don't know how to deal with that end short of cutting it off and bolting it somewhere else.

Thanks for the input!

[124JOE]

mine gave me HELL for a few months
it was the main ground
i gave the wire a tug and it came right out of the connector


i think thats your problem too.

[vandor]

Just run an addition separate ground wire between the engine and the body. That way you will know that is not the problem.
Also check that the male/female electrical connectors on the back of the ignition switch are making good contact.
It could be a failing ignition switch too... here's an article on how to rebuild them:

http://mirafiori.com/faq/content/switch/index.html

[FordPrefect]

I checked the voltage of the battery (car off) 12.12 volts. Voltage whist car is running 12.08; good indication alt isn't charging, so the little light is accurate. I cleaned the contacts on the mechanical regulator, add an extra (temporary) ground strap, and the little light goes on. Check the battery, 12.58 running, and increasing. Remove ground strap, light still goes on properly, voltage stays up.

Every time there seems to be a problem, it feels like it magically goes away without me really figuring out what I've done to fix it.

However, I think 12.5 seems a little low. Maybe the alt is too puny, the regulator isn't great or the grounds are still very poor. I guess I'll still have to play around with it. At least all of the dashboard lights seem to be working properly now. I'll wait till dark to give them a workout.

[majicwrench]

12.5 is too low, but if it is cranking out the amps the volts WILL be low. If the volts are coming up, odds are things are working. Fully charge the battery, then run it, and see what the volts are at the battery.

[vandor]

A working alternator will put out at least 13 volts, but usually more like 13.5 volts.
12.5 means it is barely working, sounds like either the alternator or voltage regulator is shot.

[FordPrefect]

After everything magically appeared to start working again, it stopped.

Funny story though, I didn't realize how much gas I used starting it and letting it run while I tested things, and nearly ran out of gas and barely had enough to reach a gas station. It chugged, missed, and generally acted really nasty on the way there and was happy that it was downhill the last half mile so I coasted in, not wanting to push it. It ran great after that, but I realized that while the needle on the fuel gauge read empty, the little light didn't go on.

So I tested the sender by grounding the wires as per instructions in another thread, and got nothing while the key was in MAR, but the light and needle were great after the car was started. In fact, all of the lights and everything work when the car is started; charging light, oil light turn on and off like they are supposed to, but they don't go on when the key is only turned to the MAR. Starting to think it's maybe the ignition switch itself. Make sense?

Now I'm considering this operation, or maybe getting a new switch. Anyone tried repairing one?

[divace73]

Now I'm considering this operation, or maybe getting a new switch. Anyone tried repairing one?

I have and it is pretty easy, there is an article on the mirafoiri forum http://www.mirafiori.com/~kdickson/switch/
which describes who to do it quite well. Instead of the log fastener and nuts recommended I went to a hobby shop and use a fastener that was better suited for the application and as the diameter is smaller the fastener tapped itself in the bottom baker light/plastic base so you can easily reuse the circlip.

Be aware of the cheap alternative that are available on fleabay, most of them are rubbish, if you can find an original sipea brand unit for a good price go for it, you’ll only need the electric/electronic portion only.

[FordPrefect]

I had the alternator tested not too long ago and was told it was working fine. After testing various things a few days ago, starting and running, etc. next day it didn't have enough power to start. So I charged it again, let it sit for a few days, today it fired up, battery had plenty of juice cold and cranking. I tested the alternator myself today while the car was running, and got around 13.2 volts.

Strangely, when I was revving it up, the engine stumbles at low revs between 800 rpm and 2k sometimes there is a click and then stumbling. Maybe that's what I was feeling when I thought I was running out of gas. It runs fine, but when you hit the gas at low rpms it has problem. Could this be related to the electrical problem?

I noticed while playing with the voltage regulator that the engine ran much smoother when I held the arm against one contact, ran rougher when I let it do it's own thing. Makes me wonder.