Car won't start, No spark

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7dartdemon2

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Changed the heads and intake on my '74 Duster and now that it is all back together I have no spark. The only wires I un-hooked during the head & intake swap were the battery, alternator, starter, and electronic dist. plug. Everything is back together correctly but the car just rolls over and doesn't fire. Everything checked out with a test light except I have no power coming out of the dist. The dist. was un-plugged and used a jumper wire on the plug coming out of the ignition box, when that was done got spark out of the coil wire. I have no spark out of the cap or plug wires.
 
There is spark out of the coil if the dist. is un-plugged and a jumper wire is run into the plug that comes from the ignition box. But if we have the dist. plugged in and we turn the key inside the car there is no spark out of the coil wire.
 
I have changed the ballast, coil, ECU, and the dist. and still no spark.
 
What Ignition system are you using? I tend to check grounds alot sooner then most people but I can't see a problem this time with that. Is the coil/box mounted on the frame. Did you connect the ground wire from the back of the passenger side head to the firewall?
 
Runnung a stock Mopar ignition system. What do you guys think about the igintion switch wiring??? There is no spark out of the coil when trying to start the car by the switch, but if the dist. is un-plugged and put a jumper wire in the plug that goes to the ingnition box then we'll get saprk out of the coil.
 
If it has electronic ignition perhaps the distributor needs to be rebuilt, the part in the distributor that has the wire attached to it. This happened to me when the key was accidently left in the accessory position for an extended period of time.
 
I agree with no ground you may have spilled something on your engine ground. I had to run a new ground wire to the engine Head, to make it work. If you painted the manifold or heads they may need new grounds. I also have got new parts that have sat to long on the selves, and are no good. So try mixing your parts around to see if any or all work. Grounds are still the most important thing, make sure they are grounded. The coil will work when any power is given to it, It just make the power stronger.
 
First, take off the distributor cap and make sure the shaft is spinning when you crank the engine. If so, next check to be sure you have approx. 6 volts at the coil + terminal when the key is in the ON position and approx 12 volts when the key is in the start position. If so, next check to see if you have continuity through the distributor pickup coil by using an ohm meter on the 2 wires that are for that circuit. I like using the ones right on the control module plug so that it tests the wiring harness also. One of those test should reveal the problem.
Good Luck, Mark
 
I'm betting my money on MVR and Redhot's diagnosis. Either the ground got left off or the paint is thick enough on those new heads to hamper the ground. The former happened to me once.
 
clifftt said:
I'm betting my money on MVR and Redhot's diagnosis. Either the ground got left off or the paint is thick enough on those new heads to hamper the ground. The former happened to me once.
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we did check all grounds and they are good. none were left off or broken. I even took the ecu box and sanded the paint off the inner fender so I new that that was grounded.
 
I Had The Same Thing A Few Years Back On My 340 Dart Sport , It Was The Red Wire On The Ignition Switch Bulkhead Under Steering Column It Was Burnt And Had A Real Bad Connection This May Be It.
 
I agree with "kt340sport" That firewall is notorious for connection problems. An easy by-pass once diagnosed is to push out the connectors at that terminal and just run a wire through. Just in case check the rotor. I had a cousin whos rotor was bad and the spark went off the back of the rotor. He just cut off the back tab of the rotor to make sure.
 
Romeo said:
I agree with "kt340sport" That firewall is notorious for connection problems. An easy by-pass once diagnosed is to push out the connectors at that terminal and just run a wire through. Just in case check the rotor. I had a cousin whos rotor was bad and the spark went off the back of the rotor. He just cut off the back tab of the rotor to make sure.
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we arent even getting power out of the coil wire so it caint be spark coming off the back of the rotor.if that wire on the bulkhead was bad wouldnt we get no power to the positive side of the coil and wouldnt the car not even roll over.
 
I still think that you got bad new parts if everything you are saying is true. New old stock can mean new old junk, Try making sure your parts are good with a multi-meter. Reading should come with your new parts.Plus to make sure your ground are good keep the key on and rub all your ground connections to see if they spark, with sparks, if not your ground is bad some where down the line. Battery cable could be white with acid even though you do not see it. If you are not sparking when you rub your grounds thats it. Jumper wire should be used to rub all your parts. All I mean All have to spark when rubbed if not thats the one bad spot. Also white acid is everywhere so clean I Mean Clean the connections...ED.
 
Also alternator could be a bad connections, Starter is also a connertion, Plus your key start could be bad with broken wire, Alternator I have to run extra ground wire to mine.I turned my 64 to electronic and the grounds to alternator stop me cold till I grounded it better. Where bracket goes to head or block may be painted or oily.Also any build up of sludge can be a quick ground and stop you cold it can be any where on the engine or firewall.
 
What I mean by rubbing all your parts is, with a Jumper wire from your battery negative side not positive. With that good of a negative connection They all have to spark with the key on. If they do not spark from the negative side of battery thats the bad connection. Do not I repeat Do Not use the positive side of battery on your ECU or Your Starter, or Alternator, or Horn Relay, Yes it can stop your power if your horn relay is bad. Starter relay, That is why you use the Negative side of battery... They all should spark when rubbed with negative side I mean all powered parts. It sparks cause it is quicker ground then you have, that way you know it is getting power. They will be very hard to see so maybe at night or in dark area, I bet its your alternator or horn relay its always over looked.Alternator has to have a great ground.It could be white acid on one of the grounds to any engine electronic part look for white acid its not your friend... ED.
 
had a 74 duster with similar problem once.went to start it and had no fire.turns out there was a bad wire at the bulkhead connector,you may have damaged a wire when you were changing parts and not realized it.i would check all the bulkhead wires.
 
I found the problem guys. It only took 3 days. The alternator was shorting out when it was turning over, thats why all my test were showing good when I wasnt turning the motor over. I even took the distributer out and turned it by hand with the key on and every wire was firing, that is when I realized I had a dead short somewhere. So I unhooked the alternator and the car fired right up. so all this time over a stupid alternator. But hey thanks guys you taught me alot and I learned alot more about how the wiring in these cars work and how to trouble shoot a problem like this.
 
You should of Tried Rewiring A Car from Points to Electronic. First I had to get a wiring harness to do it to. Then the fun of wiring it started. Thats when all the trickes of the trade come into play. Talk about 3 Days, try just thinking about it for a whole Month. Then the alternator was the last little thing to deal with.Just like your fun.Its a lot to have done but if you know the slant Six and where its Dist. is and how hard the Points are to change, you know why it was worth the trouble.And yes I kept the old system intacted...Just in case... ED...
 
Although I was not working on my A body, but instead my E body I had to do some digging around to find out why it wasnt starting. We had just put some TTI's on this week and went to start it back up and NOTHING wont start. Thanks to this site I was able to locate a thread that had all the same symptoms as we were having. During the time of installation I must have hit/moved the alternator just enough to disconnect the ground.

Thanks FABO, saved again.
 
Once you know the trade you can start trouble shooting all your Rides. It has not changed since it started,6,12,24 Volts or more. The new ones just have hid them in new names But they all pretty much do the same thing. On newer Rides that choke the air flow, I always add A 12 VDC 4" Fan after the Air Filter to pump up the Air Flow and it helps Gas Mileage by as many as 5 Miles a Gallon. This can help your engine with horsepower as well. Cold Air Induction and K/N sells them for Big Bucks. The 4" Fan put me back 5 Bucks and some wire. Always find positive Power that only works when engine or Key is on. Or dead battery. Big blocks can't get enough of that Air Stuff...ED.
 
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