No spark to turn over engine

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Carofthemonth

Carofthemonth

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74 Duster 318. Car died waiting at stop light. Getting plenty of fuel and starter will turn motor but will not fire. Things I have replaced are, ballast resistor, coil, distributor cap and rotor all new plug wires and ICM. I have also giggled all connections I could find. Still will not turn over and start. Any help greatly appreciated.
 
Sounds like it's turning over just fine with the starter motor, but, ignition is not happening, correct? Have you verified that the distributor is turning? Maybe it lost the timing chain? Which ignition system are you using? Factory electronic? If so, there is a procedure to follow when diagnosing the system. If you have a volt/ohm meter, it's pretty easy to do and should be in just about any repair manual.
 
Carofthemonth said:
74 Duster 318. Car died waiting at stop light. Getting plenty of fuel and starter will turn motor but will not fire. Things I have replaced are, ballast resistor, coil, distributor cap and rotor all new plug wires and ICM. I have also giggled all connections I could find. Still will not turn over and start. Any help greatly appreciated.
Click to expand...
Cranks but won't start? Or, cranks but won't start!
 
cudamark said:
Sounds like it's turning over just fine with the starter motor, but, ignition is not happening, correct? Have you verified that the distributor is turning? Maybe it lost the timing chain? Which ignition system are you using? Factory electronic? If so, there is a procedure to follow when diagnosing the system. If you have a volt/ohm meter, it's pretty easy to do and should be in just about any repair manual.
Click to expand...
I did take the distributor cap off and the rotor has moved. It is all stock as far as I know.
 
Let's get terms straight:

CRANK: Means the starter operates, either with key or "jumping" the rely, engine rotates
TURNS OVER: Same thing as above

FIRES: Tries to start, coughs bangs, shoots flame, or tries to run
FIRES AND RUNS: Obvious, starts and runs, and can be specified, IE "runs for a few seconds" etc
RUNS: Same as above

IF IT WILL NOT crank with the key, this is a 74, and has (had) the hated seat belt interlock. This is a reset button on a rectangular "looks like a horn relay" on the driver side fender apron. Find the two yellowish wires and splice them permanently together at the reset device connector

So does it crank with the key?

CHECK SPARK: In these situations, check spark right OUT of the coil and do NOT use the coil wire. "Rig" a test gap, either build or buy one, or use a spark plug, and "rig" with wire core wire, even if low voltage wire---you can "hang" it out in the air away from other parts. Look through the hood gap, twist the key, see if you get nice blue, snappy hot spark

If not......

You need a mulitmeter, test lamp, a couple of alligator jumper wires "in general". If you do NOT have a factory shop manual GET one

You can download the 73 manual from MyMopar for free BUT DO NOT USE the wiring diagrams in that manual, as the 73 and 74 are DIFFERENT.

I created a downloadable wiring manual but IT MAY be flawed, let me know, go here:

Free service manuals

Go to post 64, click the black icon and "save as."

CHECKS YOU CAN MAKE

Turn key to "run." Check coil + voltage to ground, It should be LESS than battery, perhaps 6-8 or maybe 10V and not much higher. Coil NEG should read LOW perhaps 1-2 V and no higher

Rig your test gap. Separate the distributor pickup connector, and take the engine bay end of the connector. Tap the BARE end of the connector terminal to a ground. You should get one blue hot "snap" spark each time you do so

Remove cap, rotor, inspect for carbon tracking, damage, moisture, rotor "punch through"

Inspect reluctor / pickup for damage, rust, debri, wobble, loose / sloppy shaft bearings.

Hook your meter to the distr. connector and crank engine. With meter on low AC (that's right AC) volts the dist. should generate about 1 volt AC

Ignition box MUST be grounded. Pull connectors loose, inspect for corrosion. "work" in/ out feel for tightness, and this will "scrub" the terminals clean
 
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Voltage tests would be my next step. Make sure you have the proper power at the ballast, and at the coil with the key in the ON position. Also check for higher voltage at the coil in the START position. Look up the test procedure for the ECM plug voltage and pickup coil resistance.
 
cudamark said:
Voltage tests would be my next step. Make sure you have the proper power at the ballast, and at the coil with the key in the ON position. Also check for higher voltage at the coil in the START position. Look up the test procedure for the ECM plug voltage and pickup coil resistance.
Click to expand...
Yes I forgot.

When cranking, the coil power goes a different route. The "normal" coil "run" power goes DEAD and the coil is powered direct from the key. So clip your meter to the coil+ and crank engine WITH THE KEY. When cranking, the coil should read "same as battery" and at least 10.5V or more
 
67Dart273 said:
Let's get terms straight:

CRANK: Means the starter operates, either with key or "jumping" the rely, engine rotates
TURNS OVER: Same thing as above

FIRES: Tries to start, coughs bangs, shoots flame, or tries to run
FIRES AND RUNS: Obvious, starts and runs, and can be specified, IE "runs for a few seconds" etc
RUNS: Same as above

IF IT WILL NOT crank with the key, this is a 74, and has (had) the hated seat belt interlock. This is a reset button on a rectangular "looks like a horn relay" on the driver side fender apron. Find the two yellowish wires and splice them permanently together at the reset device connector

So does it crank with the key?

CHECK SPARK: In these situations, check spark right OUT of the coil and do NOT use the coil wire. "Rig" a test gap, either build or buy one, or use a spark plug, and "rig" with wire core wire, even if low voltage wire---you can "hang" it out in the air away from other parts. Look through the hood gap, twist the key, see if you get nice blue, snappy hot spark

If not......

You need a mulitmeter, test lamp, a couple of alligator jumper wires "in general". If you do NOT have a factory shop manual GET one

You can download the 73 manual from MyMopar for free BUT DO NOT USE the wiring diagrams in that manual, as the 73 and 74 are DIFFERENT.

I created a downloadable wiring manual but IT MAY be flawed, let me know, go here:

Free service manuals

Go to post 64, click the black icon and "save as."

CHECKS YOU CAN MAKE

Turn key to "run." Check coil + voltage to ground, It should be LESS than battery, perhaps 6-8 or maybe 10V and not much higher. Coil NEG should read LOW perhaps 1-2 V and no higher

Rig your test gap. Separate the distributor pickup connector, and take the engine bay end of the connector. Tap the BARE end of the connector terminal to a ground. You should get one blue hot "snap" spark each time you do so

Remove cap, rotor, inspect for carbon tracking, damage, moisture, rotor "punch through"

Inspect reluctor / pickup for damage, rust, debri, wobble, loose / sloppy shaft bearings.

Hook your meter to the distr. connector and crank engine. With meter on low AC (that's right AC) volts the dist. should generate about 1 volt AC

Ignition box MUST be grounded. Pull connectors loose, inspect for corrosion. "work" in/ out feel for tightness, and this will "scrub" the terminals clean
Click to expand...
Okay, I did the spark test and no spark using a plug and plug wire to the coil. It's gonna take me a bit to do the other tests.
 
I'm in the N end of Idaho, so we are "earlier" than you (Pacific time). If you would like some "live" help while testing, be glad to yak on the phone. Send me a PM if you want and I'll give you my number I'm "up" usually around 7AM and to bed about 11PM
 
Probably a real long shot, but I once had an issue with my 74 duster 360. It would crank but wouldn't start. In my case it was happening intermittently. It turns out, the two-wire harness to the Chrysler electronic distributor got pinched beneath the cap by accident.
 
If the engine has a lot of miles AND the vac adv unit is hooked up, p/up wires may have broken. The VA unit flexes the wires, will eventually break.

Very simple to test. Disconnect dist plug & check resistance of p/up coil. Up to about 450 ohms is ok. If open cct, p/up is bad.
 
67Dart273 said:
I'm in the N end of Idaho, so we are "earlier" than you (Pacific time). If you would like some "live" help while testing, be glad to yak on the phone. Send me a PM if you want and I'll give you my number I'm "up" usually around 7AM and to bed about 11PM
Click to expand...
I won't be able to work on it again till Sunday. Be okay to contact you then if needed?
 
rustycowll69 said:
Probably a real long shot, but I once had an issue with my 74 duster 360. It would crank but wouldn't start. In my case it was happening intermittently. It turns out, the two-wire harness to the Chrysler electronic distributor got pinched beneath the cap by accident.
Click to expand...
I checked this connection seemed to good. Thanks
 
Magnetic pickup must have went bad.
Op said he change the coil, ballast resistor, ignition control box all that's left if the distributor turns with the motor cranking over is either power to the whole ignition system which he hasn't said if he's checked yet even though he changed the ballast or the magnetic pickup has failed in the distributor
 
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