not getting any spark from coil

[isaac]

i was driving and out of nowhere my car made a loud bang"
back fire"
i checked the cap and the center spring insert in the cap was
missing, igot new batery, coil,cap and rotor new coil wire and
i'm still not geting any spark.
the car turns over the same,
but it wont start .
i'v checked the wires and i cleand all the grounds
i'm a litle lost please help..........

thanks,
isaac

[John Rogers]

What are the points set at? Static check the distributor to see if the rotor is pointing at #1 mark when #1 is a TDC. Crank the engine to see if the rotor is turning? Do you have 12 volts at the coil connection when key is on? Good luck

[isaac]

yes, i do have 12v at the coil connection when the key is on ,
but nothing from the coil wire it self,
i'v checked but nothing !

[John Rogers]

What about the other suggestions I made?

[isaac]

john, yes
i tdc to the #1 pulled the cap and rotor is turning!
i'm getting power to the coil+ but still nothing out of the coil wire to the distributor .
is there away to bypass "hotwire" it ?
to make sure that the ingnition swich is not bad?
when i turn the key my red light and green light come on
but my seat belt light is not comming on when i turn the key.
and thanks for helping me i' just a litle lost
my car is never broke down like this...........

[Tidybuoy]

You might check the ground strap inside the distributor. This is a tiny braided steel wire that grounds the points contact plate to the base plate. Most 914's that I have seen have had a very brittle strap and when this breaks - no spark.

Just a thought.........................Vern

[John Rogers]

What is the dwell or points gap? If the points do not open, there will be NO spark. Measure the opening when the rubbing block is on a high point of one of the 4 bumps on the distributor shaft. If you have something like a Compufire or Pertronix points eliminator, it may have failed. In that case put a set of points in, set them and try it

[isaac]

thanks,
john i'll do that in the morning.
i have another ditributor
i'll change it just to make sure.......

[Dave at Pelican Parts]

From my reply to you in our on-line help section:

> i was driving , car gave a big backfire 'pop'
> so i pulled over , i cranked the car over and over
> it did'nt start. ....
> the car s cranks good but nspark from coil.

First, check that you have +12V on the (+) terminal of the coil, when the key is in the "on" position.

Make sure that the cap and the rotor are OK. The rotor should conduct between its center contact and the tip. Stock rotors should have some resistance here, but I forget the amount.

Next, turn the key back off again and by hand rotate the engine so that the cam inside the distributor is not pushing on the rubbing block of the points--so that the rubbing block is at the "low spot" on the distributor cam. Take an extra spark plug and plug it into an extra plug wire, then plug that into the center terminal on the coil. Tape the plug so that its threaded part (or the outer electrode) are on a ground like the fan shroud or engine case. Make sure you can still see the plug gap.

Turn the key back to on again, and use a small screwdriver to close the points, and let go so the spring on the points opens them again. On one of these transitions (when the points open up, or when they close) you should get a spark at the plug. I forget which transition... If you get a spark, then the points and condensor and coil and the wiring to those parts is all OK.

If not, then unplug the tach wire (black with purple stripe) from the coil (-) terminal and try again. This removes the tach from the equation.

If still no spark, turn the key off again and hook up a spare length of wire to a ground--like the battery (-) terminal, or the fan shroud... Unplug the green wire from the points/condensor from the coil (-) terminal. Turn the key back on again, and touch the ground wire to the coil (-) terminal and then pull it away again. On one of those transitions, the spark plug mentioned above should spark. If not, then the coil is bad or it isn't getting power after all.

If the coil is OK, but you still don't have a spark, unplug the connector between the points and the condensor, inside the distributor. Make sure that the points wire gets shorted to ground when the points close, and that there is no connection when the points open. This will test the points and the little ground braid inside the distributor.

Hope this helps.

--DD

[isaac]

dave darling,
if you where a girl you know what i'd do to you!
just joking........
thank you so much "it was the tac wire"
i don't know what the hell that was all about?
but thats what got it started "unpluged it" and the car ran,
thank you so much.

now what is it a bad tac or is it grounding some where?

thank you ,have a nice day
isaac..........................

[Dave at Pelican Parts]

Well, unplug the black/purple wire from the tach as well. Then check the resistance from either end of the wire to ground. Anything other than "no connection" means that the wire is shorted to ground somewhere. If you get a "no connection" with both ends of the wire unplugged, then the tach is likely bad. Try swapping tachs with someone else to see if that cures the problem.

Note that the tach signal wire does go through the relay board. It is unlikely, but possible, that the problem could be in the board or in the plugs to the board.

--DD

[isaac]

thanks dave you been alot of help!
i realy think that you made things so easy
all i did is read your steps and things went smooth
i didn't even have to read them over and over and over
like the stupid book.
thank you so much,
isaac.................