Engine Will Not Turn Off Options

[tdi1970]

Took 1970 1.7 to mechanic to lookover for body/frame integrity after battery leak due to voltage regulator malfunction. Mechanic cleaned battery box (what was left of new one) with water and called to tell me car will not turn off. Had car for many years and never a problem.

Mechanic replaced ignition but still will not turn off. I replaced brain/computer which did not work either. Made sure grounds were clean but otherwise, at loss??? Any suggestions?

Considering putting a kill switch in and be done with it but prefer to figure out problem.

[jmill]

Your coil is getting 12V. Trace down the 12v coil wire and find out what shorted.

[markb]

If he "turned it off" by pulling the battery cable, expect to replace the alt.

[Cap'n Krusty]

It's not just the coil, but the advice above is solid. Something's feeding power to somewhere in the fusebox where it's picked up by the keyed power circuits. The Cap'n

[Dave_Darling]

Putting a single-filament bulb into the rear turn signal bucket will result in an engine that keeps running mysteriously. Until you figure out that it's while the turn signal switch is indicating that one side, and realize that the "parking light" feature is feeding power back through the ignition.

--DD

[detoxcowboy]

Putting a single-filament bulb into the rear turn signal bucket will result in an engine that keeps running mysteriously. Until you figure out that it's while the turn signal switch is indicating that one side, and realize that the "parking light" feature is feeding power back through the ignition.

--DD

That is genius! I wonder who found that out first..

[tdi1970]

Took 1970 1.7 to mechanic to lookover for body/frame integrity after battery leak due to voltage regulator malfunction. Mechanic cleaned battery box (what was left of new one) with water and called to tell me car will not turn off. Had car for many years and never a problem.

Mechanic replaced ignition but still will not turn off. I replaced brain/computer which did not work either. Made sure grounds were clean but otherwise, at loss??? Any suggestions?

Considering putting a kill switch in and be done with it but prefer to figure out problem.

Thanks to such quick responses and hopefully solving this mystery! Will try over the weekend. Left out the part that the turn signals stopped working. Thought this was another challenge for another day. Hopefully related? Car has been EXTREMELY reliable for years and years....not used to having any trouble with it. Again, many thanks.

[ConeDodger]

I think it is kind of cruel of you to flaunt your running 914 when so many others can't get theirs to run. If you can't shut it off just keep driving. It will quit sooner or later, they all do! (IMG:style_emoticons/default/lol-2.gif)

[r_towle]

Putting a single-filament bulb into the rear turn signal bucket will result in an engine that keeps running mysteriously. Until you figure out that it's while the turn signal switch is indicating that one side, and realize that the "parking light" feature is feeding power back through the ignition.

--DD

That is genius! I wonder who found that out first..

Dave is still the king of the obscure yet factual knowledge...

That is pretty cool, almost makes me want to go read the wiring diagram....almost.

Dave, explain how a single element bulb would make this happen please..

Rich

[charliew]

It really sounds like the mechanic you used jumped to the conclusion that it wasthe ign. sw. It is a lot cheaper to find the 12vdc supply thats providing 12vdc to the coil. Just get a meter and start going back from the coil or jump ahead and take the 12 away from the ign sw. if it's that far back. I haven't looked at the 914 wiring but vw liked to get the 12vdc from the coil to supply the back up lights on the bug of the same year. It's like the back up light was a after thought and the coil was the closest switched spot for the supply to the bu lights.

If it was ok before the mech. got to it you might want to check that the alt. is not providing the 12v since that was the last thing messed with.

If there is more than one wire on the coil pull them off and check each one for the 12. If it only will happen while it's running pull them off one at a time to see which one is the culprit.

[jmill]

Just read you first post again. You had a voltage reg malfunction and the battery leaked. Did this malfunction by chance cause an over voltage situation? That would bubble over your battery alright. If so you might be chasing more electrical problems than just ignition.

[Dave_Darling]

Dave, explain how a single element bulb would make this happen please..

The "buttons" that carry the power are in different places in the single- and dual-filament sockets. I believe that the single-filament bulb contact will touch both of the contacts in the dual-filament socket. That bridges those together.

When the one gets power sent to it via the "parking light" feature, it goes to the other circuit, which is tied into the ignition switch circuit. Which means it sends power to (among other things) the coil.

Puzzled the heck out of me when it happened! I figured it out mostly by un-doing the last thing I had done to the car before the weirdness started happening.

--DD

[DBCooper]

Wow, learning by screwing up, then understanding what went wrong so you don't do it again. That's a good concept. In fact it's brilliant! If I had only thought of that when I was younger I probably could have avoided a lot of broken bones...

[Wes V]

It's not just the coil, but the advice above is solid. Something's feeding power to somewhere in the fusebox where it's picked up by the keyed power circuits. The Cap'n

I agree with the Cap and here is my guess;

Alternators have a circuit (wire) going to them that is the "energizer". When this line goes to 12v, and the alternator is turning, it puts out twelve volts in the the main circuit. When you turn off the ignition, at the key, the line should drop the 12v on the energizer and the alternator stops putting out voltage.

If the energizer line isn't hooked up seperately from other 12 volt lines, the alternator keeps feeding the system, and the car keeps on running.

Another way to say it is that the alternator "back feeds" it's self and keeps on putting out.

Wes

[jmill]

Alternators have a circuit (wire) going to them that is the "energizer". When this line goes to 12v, and the alternator is turning, it puts out twelve volts in the the main circuit. When you turn off the ignition, at the key, the line should drop the 12v on the energizer and the alternator stops putting out voltage.

If the energizer line isn't hooked up seperately from other 12 volt lines, the alternator keeps feeding the system, and the car keeps on running.

Another way to say it is that the alternator "back feeds" it's self and keeps on putting out.

Wes

Not quite. There is always voltage on the system. Switches turn it on and off but the battery voltage is always available. The alternator applies voltage to the system when the engine is running and charges the battery. It usually puts out around 14 volts. It does this by getting field voltage from the voltage regulator. The field voltage is small (alot less than 12V) compared to the voltage generated.

If the regulator goes bad and applies too much field voltage the alternator will generate over 14V and start frying stuff. Conversely if it applies 0 volts to the field you don't charge your battery and you get stuck on the side of the road when your battery dies.

[Wes V]

Put a temporary switch on the line coming out of the alternator.

With the car running, but the ignition "off", flip the switch and see if the car stops. If it does, then the alternator is "feeding" the circuit that goes to the coil.

Then take that temporary switch and put it in the line that energizes the alternator.

With the car running, but the ignition "off", flip the switch and see if the car stops.
If it does, then there is a problem with the "energizer" circuit.

Wes

[charliew]

On most cars with the indicator light on the dash it is the circuit through the light that energizes the alt. Without a good element in the light the alt won't charge. It's 12vdc but very small amps. The regulator adjust the charging through the other wire that is not the wire that goes straight to the battery. The big wire is the wire that is getting the big amps to charge the battery.

[tdi1970]

Putting a single-filament bulb into the rear turn signal bucket will result in an engine that keeps running mysteriously. Until you figure out that it's while the turn signal switch is indicating that one side, and realize that the "parking light" feature is feeding power back through the ignition.

--DD

I was going to check out car over weekend but couldn't wait. Light bulb seemed too easy. I checked and I have single filament bulbs in both rear turn signal buckets. I have double filaments in the buckets closest to the center of the car (brake and tail light). I don't recall changing the turn signal lights before problem started? I pulled each bulb one at a time, started car and turned if off and car kept running. I am not a mechanic, fyi. Have changed brakes, tuned car, replaced clutch cable but not much beyond that, especially electronic. One thing that caught my attention from what you said is that you found the turn signal problem by re-tracing changes to car before problem started. Is it possible the new voltage regulator is faulty and continuing to energize alternator?

Thanks to everyone who has posted replys, even ConeDodger. (IMG:style_emoticons/default/smile.gif)

[charliew]

I don't think I ever met anyone that could put a single element bulb in a double element socket before. The bulb has two elements and is pretty obvious. This might be beyond our communication capabilities. I would check what the mech. did and make sure none of the wires have been changed on their plugs especially the regulator at this point.

But still a amp meter is the quickest way to find this problem. You may need on-site assistance.

[tdi1970]

I don't think I ever met anyone that could put a single element bulb in a double element socket before. The bulb has two elements and is pretty obvious. This might be beyond our communication capabilities. I would check what the mech. did and make sure none of the wires have been changed on their plugs especially the regulator at this point.

But still a amp meter is the quickest way to find this problem. You may need on-site assistance.

I have an amp meter and some great ideas for starters. Mechanic was less than enthusiastic about helping me further. Pretty much told me it was not going to be his problem to figure out.