1977 Fuel Injected. Posi coming out of neg terminal on coil?

[chrisarnt]

I'm trying to get 1977 Fuel Injected convertible running.

No spark.

There is Positive current coming out of negative terminal on the coil.

I replaced the coil with a known good one and the same thing is happening?

Where should I start?

[TDCTDI]

This is normal, the points ground this "power" which causes the coil to fire. If you want to see it, ground that side of the coil & watch the high tension lead spark. Look elsewhere for your problem.
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[ashman40]

Start with voltage at the ignition coil. Turn the key to the ON/RUN position and test the black #15 wire at the ignition coil (+) terminal for 12v. Ideally, you want to see 12.6v, but anything above 12.0v would be okay.

Next, test for basic spark. Disconnect all wires from the #1 (-) terminal of the coil. Remove the center HT wire from the distributor cap and hold it near (2mm) a good ground. Using a jumper wire, momentarily ground the #1 terminal of the coil. When you remove the jumper wire from ground you should see a spark jump from the HT wire to ground. Repeat a few times to confirm. The spark should be blue-white. Red-yellow spark is a weak spark.

Next, test the distributor as a trigger for spark. Reconnect just the green (or black) condenser wire to the coil #1 (-) terminal. It should be the ONLY wire connected here. Rotate the crank by hand until the point contacts in the distributor are fully closed. Hold the coil HT wire near ground again. With a plastic or wood stick, push the points OPEN. The spark should fire. Allow them to close and re-open and a blue-white spark should fire.
If you have electric points, rotate the crank while holding the HT wire near ground. When you reach the point where the electric points "OPEN" a spark should jump from the HT wire to ground. Rock the crank back and forth across this point and the coil should produce a spark each time. Rotate the crank 180-deg and confirm each of the 4 lobes of the distributor is firing the coil.

Next, test thru the spark plugs. Replace the distributor cap and re-install the center HT wire. Remove the #1 spark plug and reattach the #1 plug wire to the spark plug. Ground the body of the spark plug (battery jumper cables come in handy). Rotate the crank until the rotor comes around to point to the #1 spark plug wire post. When the points OPEN you should see a spark jump the electrodes in the spark plug. Rock the crank back and forth around this point and the spark should jump each time. Rotate the crank 180deg to the next spark plug post. Test that plug wire and spark plug the same way. Confirm ALL four spark plugs are firing with a blue-white spark.

Next, test while cranking. Remove the distributor center HT wire. Hold it near a ground. Have someone crank the engine in neutral while you watch for spark. You should see multiple sparks as the engine cranks. If you see no sparks, weak sparks or intermittent sparks... check the voltage at the coil (+) terminal WHILE the engine is cranking. If the voltage drops below 10.0v the coil may become unreliable. If you have electronic points you don't want the voltage dropping below 11.5v. Below this the electronic points stop triggering the coil even if there is enough voltage at the coil.
_________________
AshMan40
---------------------------
'67 Beetle #1 {project car that never made it to the road }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!}

[vwoldbug]

Get a test light and touch the negative side of the coil and have someone crank the engine with the key . the test light should flash . If you have a dwell meter the needle should swing . The points may have oxidation or corossion so clean them with a points file . Then add distributor cam lube on the rubbing block and check point gap and dwell then timing .

[vwoldbug]

Do you have a Bentley repair manual.

[busdaddy]

[Starbucket]

I would run a temp. jumper wire from Batt+ to coil + and see if it starts, if it does it's probably the ign. switch is shot.

[chrisarnt]

[Starbucket]

Yes but it will keep running until you remove the jumper.

[vwoldbug]

Have you tried the test light yet . Also did you check inside the distributor and clean or replace the points . Can we get a picture of the engine .

[chrisarnt]

Test light was not flashing.

Inside of coils is clean, points clean... I think I gave it a quick spray of wd-40 when I I last fiddled with it it over a year ago.

How do I test the coil? I am not sure if the coils are getting fried?

How do I test the distributor?

[busdaddy]

No flash (steady) test light means those points aren't as clean as you think, polish them with a scrap of clean brown paper bag pinched between the contacts.

WD-4 will form a scum and degrade conductivity, especially in the presence of high voltage, try not to do that again.
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[Starbucket]

WD-40 NO! Remove the cap, rotor, points, and wipe everything with 90% Alcohol to remove all traces of oil, no wonder there's no spark. Re-grease the point cam with point cam lube.

[vwoldbug]

What is the gap on the points and do you have a dwell meter and a timing light . Also when the engine turns over is the rotor turning .

[chrisarnt]

[busdaddy]

[chrisarnt]

[busdaddy]

[ashman40]

Coil test:
Place an ohm meter on the two terminals, #15 (+) and #1 (-), and measure the resistance. Stock coil should read 3 to 4ohms.
Place the ohm meter on the #1 terminal and the center HT post. Stock coil should read 5000 to 10,000 ohms.
These as just measurement readings and do not confirm the coil is functioning. The above tests I walked thru above are functional tests. Did you try any of them?

Distributor test:
Remove the green (or black) condenser/points wire from the #1 post of the coil. With your ohm meter test the end of this wire for ground as you rotate the crank pulley and watch the points in the distributor OPEN/CLOSE. When the points are CLOSED the wire should read zero resistance to ground. When the points OPEN there should be INFINITE resistance to ground. If the resistance is not changing there is a problem with the points or condenser.
If the wire is constantly grounded, try removing the condenser from the body of the distributor and isolate it so it is not touching anything (wrap in a rag). If this allows the resistance to vary you have a bad condenser (when they fail they can open a constant path to ground).
If the wire is constantly OPEN (does not ground when the points CLOSE) then you have a disconnect somewhere along the path to ground. Try replacing the points.


Setting timing without the engine running:
Static timing the distributor to around 7BTDC is good enough to get the engine started. If your crank pulley only has a 5ATDC timing mark and a TDC "dimple"... 7.5BTDC would be about 1.5x the distance the 5ATDC mark is away from the TDC dimple, but on the opposite side of TDC.
If you ONLY have a 5ATDC timing mark (some engines don't have the TDC dimple)... mark the point 19mm CW from the 5ATDC mark. This should be approx 7BTDC.

Follow these steps to static time your distributor. You will need a test lamp.
http://www.vw-resource.com/tune_up.html#static
_________________
AshMan40
---------------------------
'67 Beetle #1 {project car that never made it to the road }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!}

[chrisarnt]

Let me say: Holy crap you guys are helpful!!!

OK. I'm on it. I have a pretty open day after 1.

I'll shoot a pick of the engine.