Need help with no spark

[scott hoffman]

Karl, I think you need to re-do your grounding. The low voltages is a tell-tale sign.

You can have continuity but still have poor current capacity. In other words, you need to clean off the contact surfaces where the ground strap is bolted as well as the other ground points.

And I'm not sure the intake is the best place to ground. Remember, what the ground strap is really for is the starter and it's bolted to the block. The intake is bolted to the heads so the current has to go through the bolts only since there are gaskets everywhere. Normally, a torqued bolt only holds by the first 1.5 thread turns. With a little grease or thread lock, the conductance can be severely diminished.

If I were you, I'd go over all the grounding surfaces and clean off the paint and apply some copper paste. If you still want the ground strap to connect to the intake, I'm afraid the paint will have to come off.

Also, I don't really see the point in having two connections to chassis. The 10Ga is either redundant OR it is the best connection to ground in which case it is insufficient which will cause low voltages everywhere, especially when cranking.

Im no electrical expert, butI would go back and read the very first comment from 318Willrun, my 340 Roadrunner was doing the very same thig you are describing. we trouble shot for HRs, low spark, used the spark light between the plugs and the wires low spark, I called a friend who is a Cheby guy he found it is like 5 minets after lightly splitting the wire case on the Nutral Safety switch, rite at the connector there were two broken wire connections, funny he said mopars are noted for this i never heard that before but some how he knew.

 

[AJ/FormS]

Since the system passes the one-spark test, at the key on/off cycle; This means the following items are good: the ECU, the coil and the all ballast connections.It also means all the grounds are working.
The only item this test does not prove is the pick up.The test for this is to trigger the pick up by passing any iron thing past the magnet. I find it easiest and most reliable to pull the dizzy out and just spin the driveshaft by hand.A stream of sparks should issue from the near-grounded coil wire. It is also possible to trigger the pick-up by passing a screwdriver over the magnet in either direction to simulate a passing reluctor vane. Of course the key will need to be in the run position for either test. The dizzy does not need to be grounded. No spark-stream means faulty pick-up. Replace it with another that has wires of the same color.These pick-ups like to break the wire strands inside the insulation,just inside the dizzy,where they are constantly flexed by the Vcan. It does not break the insulation, so the test is to lift the wire-pair up off the dizzy and stretch them out.Every sensor failure I have seen, was due to this.The sensors are polarity sensitive.They are coded by the wire colors. SBMs should be Orange and Green.
As to the no-crank issue that is another circuit.
As to the mismatched rotor orientation, I have seen that too. Correction can be made by re-orienting the oilpump drive gear.Check your rotor-phasing. Make sure the engine runs with full advance and full Vcan advance, both together, before sending the car home.I rev it up to 3600 to 4000 and read the timing. I have seen total timing this way of near 60degrees on the DB lite.I have had to reorient the reluctor in some cases.
As to the dual ballast resistor; in Run, one side reduces voltage to the ECU while the other side reduces voltage to the coil. Reduction is not instant. It is slowly reduced by the heating up of the resistors. When the resistors are cold they pass nearly full voltage to their respective users. In Crankmode the resistor to the coil is bypassed, so that if the resistors are still hot from the previous shut-down, the coil still gets near-full battery voltage.The reduced voltage allows the components to run for many years without failure. Since these components are designed to handle full battery voltage during the warm-up period, they will handle all the testing you care to do, and as one member said, can travel many miles at full voltage.

 

[krazykuda]

Ok, tried again today...

We scraped the paint from out from under the ground wires on the engine, tested it and got spark...

So we got it started and it ran for 8 minutes and died. I think we ran out of gas, the plastic filter showed no gas...

We put 10 gallons in and tried to restart, and we're back to no spark again....

We tried another ballast resistor and an orange box, and nothing....

We are still getting power to both sides of the ballast, and the positive coil post, but can't get spark...

What could do this????

 

[Bad Sport]

Finish cleaning up the grounds. Firewall and where the ECU is mounted.

Like I said on the ECU, you can run a machine screw through the inner fender and clean the outside to bare metal, use one of those washers that dig in on that. OR, run a ground wire, that's what I have on mine.

 

[AJ/FormS]

Does it still pass the one-spark test?

 

[Eddie348]

Bad Sport & AJ
Bad Sport - grounded the ECU with a cable from the negative side of the battery
AJ - still passes the one spark test
Thanks

 

[krazykuda]

We tried running a daisy chain of banana jumper wires from the ecu box screw to the battery ground - still no spark...

We tried another distributor and it did spark, but since it was the ones that are clocked 90° off, we redid the wires on the cap to match the new rotor position, and then no spark...

Is there a way to test the control boxes, distributor pick-up, coil, and ballast resistor to determine if they work properly or not? AutoZone? O'reily's??? Would they have a tester that could help us???

 

[Daves69]

Do you have a tach or limiter installed?

 

[krazykuda]

Do you have a tach or limiter installed?

No.

 

[Bad Sport]

Is there a way to test the control boxes, distributor pick-up, coil, and ballast resistor to determine if they work properly or not? AutoZone? O'reily's??? Would they have a tester that could help us???

To check the pick up coil. Unplug the 2 way connector, set your meter to Ohm's, 1 lead on each wire. You should see 150 to 900 Ohms.

Set your meter to AC volts, 1 lead in each hole, spin the dizzy by either turning the engine over or pull the dizzy and spin it by hand. You need 1 volt AC minimum.

Ballast resistor, set to Ohms, one lead on each end, take reading.

 

[Bad Sport]

You should also check for 12 volts at pin 1 of the ECU connector when the ignition is in the "on" position. It is also important that the ECU be securely bolted in place and that bolts provide a good ground to the ECU housing. The only other lead that is connected to the ECU is the "-" lead to the coil, which can be checked to insure that it is not broken.

 

[krazykuda]

To check the pick up coil. Unplug the 2 way connector, set your meter to Ohm's, 1 lead on each wire. You should see 150 to 900 Ohms.

Set your meter to AC volts, 1 lead in each hole, spin the dizzy by either turning the engine over or pull the dizzy and spin it by hand. You need 1 volt AC minimum.

Ballast resistor, set to Ohms, one lead on each end, take reading.

Both of these checked out ok...

 

[krazykuda]

You should also check for 12 volts at pin 1 of the ECU connector when the ignition is in the "on" position. It is also important that the ECU be securely bolted in place and that bolts provide a good ground to the ECU housing. The only other lead that is connected to the ECU is the "-" lead to the coil, which can be checked to insure that it is not broken.

We are getting the same voltage on the blue wire of the ecu as we see at the input side of the ballast about 11v...

 

[mycuda]

Ok, tried again today...

We scraped the paint from out from under the ground wires on the engine, tested it and got spark...

So we got it started and it ran for 8 minutes and died. I think we ran out of gas, the plastic filter showed no gas...

We put 10 gallons in and tried to restart, and we're back to no spark again....

We tried another ballast resistor and an orange box, and nothing....

We are still getting power to both sides of the ballast, and the positive coil post, but can't get spark...

What could do this????

Gotta be coil or dizzy.
flip a points dizzy in. Bet it runs

 

[krazykuda]

Gotta be coil or dizzy.
flip a points dizzy in. Bet it runs

Unfortunately, I don't have a points dizzy in running condition...

We did try to install the dizzy from my MP elect ign kit, it got spark initially with the cap and wires from the other distributor, but when we installed the cap for that dizzy and repositioned the wires for the 90° off rotor, it would not spark again....

 

[krazykuda]

Here's a short video of when we got it started earlier today, before the problem came back, this is at initial start, without setting the timing yet...

 

[mycuda]

Unfortunately, I don't have a points dizzy in running condition...

We did try to install the dizzy from my MP elect ign kit, it got spark initially with the cap and wires from the other distributor, but when we installed the cap for that dizzy and repositioned the wires for the 90° off rotor, it would not spark again....

Somthin crazy goin on there.

 

[krazykuda]

Somthin crazy goin on there.

Yep, and it's driving us nuts....

 

[RustyRatRod]

Is this a new engine startup? No way should you be letting it idle. I wonder how many flat cam lobes you will have now?

 

[mycuda]

I havent been on top this thread, but did you put 12 volts to coil from battery and try?

 

[AJ/FormS]

If it passes the one-spark test, it has to be either a faulty sensor, or a failure of the sensor to trigger, or a polarity reversed sensor.I have never seen it different.
You can plug in the spare dizzy and hand-crank it to produce a stream of sparks from a near-grounded coil wire. The key needs to be on, engine not running. The dizzy does not need to be grounded. This is a lotta fun. zzzzzzzt,zzzzzzzzzzt,zzzz zzzz zzzzzzzzzt,zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzt

You can set the initial timing with polarity reversed, but 1) the timing will not be where you expected it to be,on start-up, and 2) the engine will not take throttle, more than a couple of hundred rpm. If you watch the timing marks at this time, you will see why. It will be jumping all around, even retarding, and completely skipping some sparks.It will, however, idle pretty good.

 

[nm9stheham]

Karl:
1) Do you have a picture of the ballast or a PN?

2) One thing to note: there is a missing wire in your original schematic back early in the thread; it shows in the schematic that Bad Sport posted in post #61 and is labeled 'IG2' at the ignition switch. It is a brown wire in the original harness, and connect to the low voltage side of the ballast that also connects to the coil+. You bypassed the ballast in one test so this is not likely the issue but it needs to be fixed. It provides +12 direct to the coil + when cranking for a hotter spark.

2a) If you have a tach, disconnect that and see if the system will fire.

3) You can segregate the problem somewhat with the following test to help focus better on the problem area:
Disconnect the coil - wire from the Mopar box (and anything else like a tach). Put the key to RUN, and using an alligator jumper grounded at one end, touch the other end to coil - and look for a spark each time you remove this ground connection from coil -. (Don't be touching the jumper end when you remove it!) If you get a spark each time, then the coil and ballast are good and you can focus on the box and distributor.

4) How are you testing for spark? I'd disconnect the wire from the coil out of the distributor and put the open end 1/4" from ground and look for a good blue spark. This bypasses any issues with the distributor cap. Don't test at a spark plug in open air; this does not at all simulate what the spark really has to jump in a compressed fuel-air mixture.

 

[TrailBeast]

Turn the key to run. Hold the coil HT wire near ground. Separate the distributor connector, and take up the vehicle side (not the dist end). "Tap" the bare connector terminal to ground. You should get one spark "snap" each time

I don't think I ever saw if this method was used to check the ignition box (or if it was just by the key being turned off)

Take a look at this and please verify the locations are correct on your distributor.
Ignore the fact that it is a dual pickup, as I just need to verify the roll pin and markings on the reluctor are in the right orientation.

Sorry I didn't realize this was one of my advance modded distributors or I would have commented sooner.
EDIT: Also know that the distributor is set up for a min 14 degree intial advance and 18 more on the limiter plate for an approximate 32 degree total without vacuum added yet.
And that the orientation of the shaft end is probably because in remanufacturing they may have turned the pinned retainer on the shaft 90 degrees and drilled a new hole for that roll pin (seen it before) but it makes zero difference in the function of the distributor (you just change the wires to match like you already did)

 

[krazykuda]

Is this a new engine startup? No way should you be letting it idle. I wonder how many flat cam lobes you will have now?

Yes, fresh start up, but it didn't idle long. as soon as we verified no major oil, trans fluid, and water leaks, I set the RPM's up to 2150 to start the cam break in....

Here's the video of when I got the RPM's up and the timing set to 35° at 2150 RPM...

 

[krazykuda]

Thanks for the replies guys. We will check them out later and report back...