Electronics Gone Wild - HELP!

[Ranger]

OK guys, put on your electrician hats (electrical is not my strong point).

Took her out for a rid today. After initial start up and a few idle adjustments she seemed to be running fine. Went down to Keytone in the next town to get a can of paint mixed for the trunk. On the way there I notice the tach jumping a bit, but could not notice any misfire. Now on the way home (about 10 miles each way, all highway) she starts missing pretty bad. Tach is bouncing up around 6000 and then 8000 and finally goes limp pointing straight down. Thought I had fried it, but it cam back to life after I had to stop for a light and the RPM cam back down. Ammeter is dead center with no movement, but the volt meter is bouncing near 17v. If I add any electrical load like the fan, the misfire gets worse and if I put the headlights on, it almost flat lines. It seemed to get worse the longer I drove it and as the battery got fully charged. Now keep in mind, that I just drove it from DTW last Dec. (I know that doesn't necessarily mean much). Does this sound like a voltage regulator problem?

 

[bigmanjbmopar]

Does this sound like a voltage regulator problem

Yes, and overheated ballast resistor. Also sounds like a burned up plug wire or two. Are you still running points on the distributor?

 

[bigmanjbmopar]

Does this sound like a voltage regulator problem

Yes, and overheated ballast resistor. Also sounds like a burned up plug wire or two. Are you still running points on the distributor?

 

[Ranger]

No, I'm running a Mopar Performance pointless electronic ignition. Similar, if not identical to this one.



Why would you suspect a bad plug wire?

I just checked the resistor. It is nice and white and did not show any signs of overheating. I even dismounted it from the firewall and checked the back side. Looks like new.

So my question is, if it is the voltage regulator, can you explain how that causes the misfiring and worsening when an electrical load is applied? My limited electrical knowledge would tell me that bleeding off current would make it better.

If you are fairly confident that the regulator is at fault I will gladly get a new one as it will be a cheap and easy fix. Any recommendations? The Wells VR706 electronic regulator was recommended in my earlier voltage thread in this forum.

 

[Big John]

If you have 17 volts, it may be too much for the ECU.

The electronic ignition doesn't like mechanical regulators. I suggest going to a Wells VR706.

 

[Ranger]

Thanks guys, suspicions confirmed. I'll pick one up or order it today. Then it's on to the cam.

 

[Ranger]

I just ordered the VR706 on Ebay. Sure hope that's the problem because I just went out to check it and the car is DOA. Absolutely no power to anything. Not sure if a bad regulator can cause this, but I sure hope so.

 

[A12]

Maybe a combination of a bad voltage regulator and a cooked battery and/or a bad alternator too....ouch. The symptoms almost sounded to me like the car was just running off of the battery all of that time, except for the 17v showing on the gauge???

 

[Ranger]

Checked the battery today. It has 12.4v.

I had considered it running off the battery, but the 17v would lead me to believe that not to be the case and "should" rule out a bad alternator. Seems to me it was putting out all it could. I guess I'll know for sure when I get the new regulator installed an open the door (praying to see a dome light come on).

 

[Ranger]

Well, the new voltage regulator came today. I installed it with high hopes, but they where shattered. The car is deader than a door nail. I have battery voltage to the fusible link on the firewall. Something beyond that must be fried. I'm going to do some more digging in the FSM. Anymore ideas would be greatly appreciated.

 

[Ranger]

Follow up & closure:

Well it's fixed and I have power again. As I said, I traced power to the bulkhead connector on the firewall, so I new it had to be in the cabin. Reached under the dash on the left side of the column, and as I moved wires, the lights came on. Apparently nothing was fried, and like A12 said, it was a combination of problem. Good news is nothing was fried. Bad news is I don't know what was loose or exactly how I fixed it. What a load off my mind.

Next step will be to take her for a ride and see how the voltage acts.

 

[A12]

Just thinking out loud here; you have battery voltage to the fusible link and on the other side of the fuse.....then to the junction block, starter relay and power into the interior of the car? Is the engine (-) ground good to the battery and at the block/intake manifold? Just working with the most basics, you have a battery that gets 12v to the ignition, then to the starter relay, cranks the starter and 12v to the coil and starts the car and then the alternator takes it from there to provide the 12v. The battery supplies everything up until the engine is spinning the alternator...............what's missing? What's keeping the battery voltage from getting to the starter and beyond....maybe a bad ignition switch?

 

[A12]

Forgot to ask if you have lights or any other 12v power that doesn't require the key switch to function?

 

[Ranger]

No no, you're misunderstanding. I HAD power to the bulkhead connector on the firewall. EVERYTHING beyond that was dead. No crank, no lights, no nothing. Same as if you pulled a battery cable.

After I jiggled the wires under the dash, all is well again.

 

[quikbird]

If it works when wiggling wires, you have loose wire/short somewhere. Can be dangerous and fire hazard. Please go find the bad connection. You will sleep better not worrying if the car is about to be a crispy critter

 

[A12]

Ranger, don't take this the wrong way but you haven't fix your problem you've only located it. If jiggling the under dash wires made it well again then jiggling the wires will make it happen again and that's a very dangerous situation. I would really get under the dash and check it out and fix the loose wires or connector or whatever you jiggled to make the connection again. I'll find the photo of my GTX's under dash wiring harness and show you how close it came to lighting up the car. And if the car didn't crank just because of a loose connection I would hate to have it not crank in an emergency. Check it out, it may just be a simple fix.

 

[Ranger]

You guys are right. I took it for a ride today and the voltage gauge stayed nice and steady, right about 14.5v, so the Wells VR706 fixed THAT problem.The ammeter stayed on the charge side.
About 5 min. down the highway, she flat lined. Tack went to zero and lost all power. Coasted off to the shoulder. Naturally my first response was to reach under the dash and she eventually lit. No problem on the way home. God I hate this. It's so tight under there, hard to see upside down and my hands are to damned big to get in there, not to mention it's a rats nest, but I have to figure it out somehow. Praying for a simple fix. Just not sure where to start.

On an unrelated note, does the volt gauge draw any power? I noticed I have mine connected to a spade on the back of the fuse box (hot all the time). Not sure if that is detrimental as in battery draw or if it has to be hot only when the ignition is on.

 

[Big John]

The volt meter does draw a minute amount of power. Not enough to drain a battery, but I have always wired them to only be on when the key is switched on. Switch it over to the spade on the other side of the fuse block. That one is "switched".

Here's a tip... pull the seat out to make it easier to get under the dash... Four nuts and it's out. Sooooo much easier then.

 

[Ranger]

I'll look for that spade John. Thanks for the tip.

I've had the seat out once already. It would make it easier getting in and out, but not much help under the dash. It may come down to that though if I have to camp out down there much longer.

 

[Roadcuda]

This might be worth checking. I had a similar problem with my '64 Barracuda. It was either no voltage , good voltage or weak voltage. And that changed any time I wiggled the wires under the dash. It turned out to be a loose connection on the back of the ignition switch. I tightened up two small bolts and it has been fine since.