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Thu Aug 03, 2006 8:03 am

Why is my coil not getting 12v? I think that this is the source of my car dying and sputtering bad. Thanks.

Thu Aug 03, 2006 8:20 am

It shouldn't

the coil runs on aroung 6-8volts because the igintion condensor can't handle too much power, the points would fry.

unless you have less than 6V, you're OK.

BTW the voltage should drop a little as the engine is reved up, thats normal too.

Perhaps your coil has too much resistance or the wires are failing, I had some POS EMPI "performance" wires on my project bug from when I got it and the car popped and ran like crap, threw OEM Boschs on and it purred

Thu Aug 03, 2006 8:39 am

vwdmc16 wrote: It shouldn't

the coil runs on aroung 6-8volts because the igintion condensor can't handle too much power, the points would fry.

unless you have less than 6V, you're OK.

HUH ? A 12v car should get at least 12.1 - 13.8v to the coil on a good day. There is no resistor or voltage reducer before the coil. Voltage to the points has nothing to do with the car sending 12 volts to the coil. The power to the points is handled within the coil through a resistor. Some cars such as 60-70's Chryslers even did this with an external "Ballast" resistor. You need to have close to 12v to the coil on a 12v vehicle. Test the wire to the coil, it comes off the #1 left fuse (terminal 15) on the non fused side fuse box. Run a jumper wire from the battery and see if it helps. Yes low voltage can cause some problems but if the volts are too low at the coil it won't fire the plugs.

Thu Aug 03, 2006 9:10 am

many VWs have resistor wire going to the coil, my ghia does, my project bug does, and a '67 ghia I restored did too.

Running with a full 12+ volts will work but the points life will be shortened but you will not feel any difference in the engine power withe the extra 4-6 volts.

But what the hell try hooking up a jumper wire to a real 12v source too see how it runs, it would help track down the problem

Thu Aug 03, 2006 12:13 pm

vwdmc16 wrote: many VWs have resistor wire going to the coil, my ghia does, my project bug does, and a '67 ghia I restored did too.

I've never seen a beetle with a resistor wire going to the coil. And I've seen quite a lot.

Thu Aug 03, 2006 2:12 pm

If your VWs have resistors then they have improper ignition coils, plus the resistor would need to be in the points wire (-) AFTER the coil not in the (+) wire before the coil. Reducing the coil's input voltage only serves to reduce the quality of the spark. You want the resistance AFTER the coil in the points wire so the points do not pit. The stock VW coil has the resister built into it.

Thu Aug 03, 2006 2:18 pm

vwdmc16 wrote: many VWs have resistor wire going to the coil, my ghia does, my project bug does, and a '67 ghia I restored did too.

Running with a full 12+ volts will work but the points life will be shortened but you will not feel any difference in the engine power withe the extra 4-6 volts.

But what the hell try hooking up a jumper wire to a real 12v source too see how it runs, it would help track down the problem
do you mean the wire going to the condenser?..... I have 12 volts+- on ALL of the cars in my "lot" including 4 aircooled VW's

Thu Aug 03, 2006 8:47 pm

dirty wiring at ing switch, bad ign switch, excessive resistance in wiring between battery and ign switch or between switch and coil. Yes you should have FULL battery voltage at coil,resistor is built into coil to limit CURRENT to points. Condensor is rated for 150volts so 12 volts wont be a problem

Fri Aug 04, 2006 6:10 pm

well whatever, my ghia has around 8volts at the coil, and it works great with the german bosch blue coil and 034 dizzy

Fri Aug 04, 2006 6:22 pm

vwdmc16 wrote: well whatever, my ghia has around 8volts at the coil, and it works great with the german bosch blue coil and 034 dizzy

you have a wiring problem. unless it was added the wire should not contain a resistor....if it does, then its not "fine" and should be fixed properly.....