No spark and i can only get 5V at the coil.

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YoungDart75 said:
Well after this im going to be trickle charging the battery tonight and then having it load tested tomorrow first thing.
All the below voltages were taken while turning the motor over attempting to start it. This was immediately after the battery read 12.1V with key off and not under load.
Battery power = 8.4V
Power to coil + = 7.2V
Power from negative coil to ground = 1.8V
Power to ignition(red wire) = 8.4V
Power from ignition(brown wire) = 7.7v
Ecu case voltage(case to ground)= 1.5 millivolts

The reason im load testing the battery tomorrow is because the damn thing isnt sending enough damn power through the systemin the first place during the starting process. So i cant expect any of my other readings to be proper without getting what they need. This would also explain why the 12v jumper wire to the coil didnt work either, because it was never 12v. Will update again tomorrow morning. Also nm9 ill check ur test after i find out about this battery. Thanks for all the help so far guys. Greatly appreciate it.
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Did you read the link in put in POST NUMBER 3?:banghead:
Looks like your problem at this point is ........drum roll.....weak battery.
At least part of it. Things stack up on these old cars.

Now on my "problem", if it matters.
What I do is pull the yellow wire off the start relay and just check voltage at "run" at the ballast.
Or go upstream to other points I can get to and make an educated guess.
For example I had 12 volts at the car side of the column connector. So that ruled out everything back to the bulk head disconnect.
After reseating my steering column connector and a little cleaning on the bulkhead (damned Packard blade connectors) I've now got over 11 volts at the ballast.
Of course the starter isn't engaging when I do that. But my car starts fine with a new battery.
 
nm9stheham said:
With the key in the RUN position, the brown wire will show the coil+ voltage back up through the firewall and to the ignition switch; this is because that brown wire is not connected to anything by the ignition switch in RUN and the coil - voltage backfeeds back to the switch terminal.

But your reading of only 8.7 volts on the brown wire and at the coil + is a possible sign of an issue. It should be close to battery voltage which will drop some when cranking but normally not that much.

2. Please do the test that I asked a couple of days ago so we can move forward some and start sorting out what is good and bad. Place the spark wire from the coil 1/4" from metal and remove the wire from coil -, then put the key in RUN, and then use a jumper or screwdriver to ground and unground coil - . See if you get a spark each time you do this. Don't be holding the jumper or screwdriver blade when you do this or you will get zapped. This will tell us more of what is good or bad in the system.
I did that test and when the ground is made the arch is there in the power wire from the coil when its about 1/4 from a ground
3. Test the coil resistance please. Do this with the coil - wire disconnected.coil resistance is 1.3 ohms

BTW, the irregular arcing is not normal and is the symptom of not running.
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I did your test cor the coil and it passed. Then i pulled the wires and checked spark at 4/5/6 and got no spark to either of those 3. Swapped to a known good cap and rotor and still no spark at the plugs. Right now im thinking the distributor may be the issue. Not buying parts just yet. Going to double check timing again too.
 
Ok, first off your making this more of a mess than it is. The OP had the car running at some point and then it started having issues then dies. Hence no spark. I would not ever start with wiring. you run into messes just like this. Obviously he has a bad part in the system. He should have found the bad part first then clean up the wiring after. Now he has no clue what to do because he has disturbed all the wires. Start back a square one if possible and go from there. I am a aircraft electronics technician and do this stuff daily. People that go straight to wiring have no clue how to troubleshoot. eliminate the easy first then start shooting wires.
 
did he check to see if the plastic gear on the dist sheered off? and wont send a ground signal to the ecu if its not turning.
 
teringer said:
did he check to see if the plastic gear on the dist sheered off? and wont send a ground signal to the ecu if its not turning.
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He said he verified the dist/rotor is turning on the previous page.

I'm going to agree with the bad battery diagnosis but it may not be the reason it won't start. It should rest at 12.6+ and not drop under 10.5v while cranking.

If you're only getting intermittent sparks from the coil wire itself (you should be getting quite a few of them and consistently) then there's two things to look at: voltage, which is already suspect; or the pickup in the dist. I would suspect something to do with triggering the coil, which means looking at the pickup. Some of the weird wiring, like the coil wires going in and out of the firewall, tells me that it probably had an aftermarket ignition at some point but then it was removed and they half-assed the removal. Probably also explains all the ECU splices.

Take some pictures of the inside of the dist and if you have some feeler gages (brass, preferably, since things are magnetic in there) check the clearances to the pickup.
 
Are you talking about the rotor inside the distributor and the pickup coil?

Ive taken the measurements where they needed to be taken and found a hack job in the wiring while looking it over so i fixed it where it needed to be.

Currently getting less than 12v at coil + when starting.
Not getting spark at the plugs.
Known good cap and rotor
Air gap set at .008 with brass feeler as specified
Reset timing at TDC then reinstalled distributor.

Things to note
Rotor inside distributor seems a little worn and uneven
Battery drops to 8.4-8.9 when starting (dropping the power to +coil to match accordingly)
 
64cudaV8 said:
Ok, first off your making this more of a mess than it is. The OP had the car running at some point and then it started having issues then dies. Hence no spark. I would not ever start with wiring. you run into messes just like this. Obviously he has a bad part in the system. He should have found the bad part first then clean up the wiring after. Now he has no clue what to do because he has disturbed all the wires. Start back a square one if possible and go from there. I am a aircraft electronics technician and do this stuff daily. People that go straight to wiring have no clue how to troubleshoot. eliminate the easy first then start shooting wires.
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http://www.forabodiesonly.com/mopar/editpost.php?do=editpost&p=1970886670

Me too, once upon a time in the old west. A/P FCC.
But that is neither here nor there.
I just tell that to let you know I feel your pain.

I'm guessing he MAY have more than one problem now.
Not the least of which is low starting voltage.
That ECU probably won't fire with 8.9 volts.
In all fairness, his wiring may be an issue too.
He needed help via having good prints about what it should look like to run.
 
YoungDart75 said:
Battery drops to 8.4-8.9 when starting (dropping the power to +coil to match accordingly)
Click to expand...

That's not good, but should be enough to get it to fire. Are you still not getting spark at the plugs or coil? Have you retried the +12v jumper to bypass the ballast since recharging your battery last time?

Sounds like your airgap etc is OK.

I would remove the #1 plug and make sure your engine is actually at TDC with the rotor pointed at the #1 wire. It's common to have the TDC marks not align and this could cause you tons of grief. This only applies if you're getting spark at the plugs though. The mention of the coil not firing consistently is alarming, since it should make mucho sparks when cranking..

If it's not, then something more than voltage is amiss. If you have power to the coil and the ECU is properly grounded and connected to the coil it should run. Do you have a spare ECU to try? It sounds like you tested the one you have, but that's not guarantee it's good. I wouldn't run out to buy one right away, but if you have one to swap it might help narrow it down.

If you've got a decent auto parts store in town, they may agree to let you return a new module if it doesn't fix your issue. Some places are real hardasses, but way back when I worked behind the counter I would often do this for customers to help troubleshoot an issue.
 
adriver said:
http://www.forabodiesonly.com/mopar/editpost.php?do=editpost&p=1970886670

Me too, once upon a time in the old west. A/P FCC.
But that is neither here nor there.
I just tell that to let you know I feel your pain.

I'm guessing he MAY have more than one problem now.
Not the least of which is low starting voltage.
That ECU probably won't fire with 8.9 volts.
In all fairness, his wiring may be an issue too.
He needed help via having good prints about what it should look like to run.
Click to expand...

Agreed but if the engine cranks over it should fire. However not a certainty. That's an easy check with jumper cables.
 
YoungDart75 said:
I did your test cor the coil and it passed. Then i pulled the wires and checked spark at 4/5/6 and got no spark to either of those 3. Swapped to a known good cap and rotor and still no spark at the plugs. Right now im thinking the distributor may be the issue. Not buying parts just yet. Going to double check timing again too.
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OK that shows that the coil and power feed to the coil is essentially OK. The 1.3 ohm resistance reading of the coil primary is a good number.

What you have done by grounding the coil - (while disconnected from the ECU and distributor) and getting consistent spark out of the coil spark wire is to isolate the problem to those 2 units. The 'no spark at 4/5/6' verifies this. So you now need to concentrate on the ECU and distributor pickup.

1. Does the ECU have a good ground? Remove it and scrape it and the chassis under it clean and put in new bolts, preferrably with star washers.
2. Clean out the connector contacts to the ECU module and to the distributor pickup. Look inside the female pins to make sure they have not been spread open; if so, squeeze them to tighten them up.
3. I think you made the FSM resistance test of the pickup coil earlier; is this correct?
4. There really is not an easy way to test the ECU by itself. At this point, I would check voltage and continuity of wires to the ECU connector pins if you have not already done so.
5. BTW, you can eliminate the cap and plug wires as the issue by simply connecting it all up and cranking but take the spark wire out of the coil and set it 1/4" from metal. If you get no spark or erratic spark then the issue is not in the cap or rotor. I think you already did this but with a very weak battery, so I would recommend repeating it.
 
64cudaV8 said:
Obviously he has a bad part in the system. He should have found the bad part first then clean up the wiring after. Now he has no clue what to do because he has disturbed all the wires. Start back a square one if possible and go from there.
Click to expand...
Not really arguing here..... As an FYI, this car has a bit of a history of low voltages and wiring issues, going back a while. Symptom descriptions pointed to voltage issues at the beginning of this round, so that was tackled.
 
I've run thru this thread kinda late,so if these things have been suggested/tried
already forgive me.
1)are you getting a signal out of the pick-up coil?Disconnect the 2 wire at the
dizzy and ohmmeter the dist PU ,if the reading is in spec.,crank the eng.
and you should see a definite rhythmic variation in the reading.Was much
easier to check w/analog sweep meters,but digi's w/a bar graph work ok.
otherwise you just have to watch the numbers change.
2)pull the coil wire from the dist. cap,get a test plug in the end, then attach a
jumper wire to coil negative. Turn the key to run, then tap the jumper to the
batt. neg. post in a short rhythmic fashion, if it fires a blue spark the ballast
and coil are not the problem.Either there is no signal from the pick-up,or the
module isn't doing its job,due to a poor ground or internal failure.
3)don't feel bad about attacking the halfa** harness, and be sure to check all
the module wires to their destination.It's entirely untrue that your shoddy
wiring could't be the cause of a "sudden" no start,a poor connection works
until time, oxidation,vibration stops it from barely getting it done.Then it's
done.
 
Phreakish said:
That's not good, but should be enough to get it to fire. Are you still not getting spark at the plugs or coil? Have you retried the +12v jumper to bypass the ballast since recharging your battery last time? I havent retried the jumper because the battery was still dropping to 8.xx volts so even running the jumper would only give me the 8.xx volts the battery is sending through the rest of the system anyway.

Sounds like your airgap etc is OK.

I would remove the #1 plug and make sure your engine is actually at TDC with the rotor pointed at the #1 wire. It's common to have the TDC marks not align and this could cause you tons of grief. This only applies if you're getting spark at the plugs though. The mention of the coil not firing consistently is alarming, since it should make mucho sparks when cranking.. when it is connected regularly and the power wire from the coil to the distrobutor is held 1/4" from ground it doesnt fire frequently

If it's not, then something more than voltage is amiss. If you have power to the coil and the ECU is properly grounded and connected to the coil it should run. Do you have a spare ECU to try? It sounds like you tested the one you have, but that's not guarantee it's good. I wouldn't run out to buy one right away, but if you have one to swap it might help narrow it down.
The other one i have i think ia the original 5 pin one that the PO said was bad

If you've got a decent auto parts store in town, they may agree to let you return a new module if it doesn't fix your issue. Some places are real hardasses, but way back when I worked behind the counter I would often do this for customers to help troubleshoot an issue.
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New update after a looooonnnng time of charging the battery it finally showed green for fully charged. Right now it is currently getting 10.4V at the battery when starting and 9.2V getting to the coil when starting. Im uploading the pictures of the crank and position of the rotor on the distributor when at TDC. Im also uploading a video of the power wire from the coil held 1/4 from ground while starting so you van see the frequency that it fires (or lack thereof).
 
@killer6
The reading i got out of those two wires on the pickup was 289ohms and the book call for between 150-900. So check there, but ill have to try you other suggestion.
I did the jumper test on the coil wire and it fired blue spark along with rhythmic grounding.
All my readings have gotten better since fixing the issues i found in the harness.
 
just a thought if you are getting a green eye on battery that means only one cell is at lease 60% charged ,load test the battery with a carbon pile tester .most auto stores will do it for free.
 
It tested good at advance when I took it there but the charge was low so I slow charged it longer. Thats when it finally showed green and I began getting 9+ volts at the coil when starting and the drop at the battery when starting was only down to 10.5V.
 
YoungDart75 said:
the drop at the battery when starting was only down to 10.5V.
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^^ good. That's the 'bare minimum', so you might yet get this licked.

Since you removed the distributor, you may have to tweak it a little (wiggle it back and forth slowly while someone cranks it) to get it to fire. It's also not uncommon to get it 180 degrees out, which is why it's a good idea to verify you're at TDC with a spark plug removed vs the balancer marks. It's also possible you were at TDC on the exhaust stroke... so once you start getting a good spark from the coil, if it still won't start with a little twist of the dist, I'd lift the dist and twist the rotor 180 degrees and try it all again...
 
YoungDart75 said:
p at the battery when starting was only down to 10.5V.
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?ONLY? That ain't all that GOOD. Didn't you say this was a new battery rated at 6xx cranking amps? Hell that thing ought'a maintain nearly 11 cranking that little bitty thing.

Now don't get me wrong, it should crank, start, and run on 10.5V. It's just that I would have thought that battery would do better

Dammit I've told you this before. FORGET the car harness / wiring.

GET the thing troubleshot ONLY with the ignition harness

WHAT DO I mean by that?

THIS is all you are concerned with until you get spark and fire

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Take clip leads. Jumper across the ballast. Clip the coil + to 12V. If you cannot get spark, you need to troubleshoot "that much" of it until you do.
 
67Dart273 said:
?ONLY? That ain't all that GOOD. Didn't you say this was a new battery rated at 6xx cranking amps? Hell that thing ought'a maintain nearly 11 cranking that little bitty thing.

Now don't get me wrong, it should crank, start, and run on 10.5V. It's just that I would have thought that battery would do better
Click to expand...

It definitely should do better, but it's up from ~8v which is a big improvement. Sounds like the battery was very flat - another issue to figure out once it's back to running. Oh, and I hate those 'green ball' batteries. Useless.. every customer I ever had in the past with one of those damn things thought it HAD to be good, but bad batteries were probably at fault for the vast majority of "old car" problems. If it wasn't the battery, it was crap grounds, and if not that it was wire nuts used on a million splices and ford relays randomly spliced into the harness any place one could be bolted down.

It sounds like spark might be improved from the coil too, but I'm waiting on the promised video vs reading between the lines :/ it should definitely clear up whether the ignition ecu circuit is working or not.
 
This all gets down to the basics, when it won't start

COMPRESSION. You need so much compression. This is open to discussion. Some say more than 75 psi, some say an old worn engine will run with as little as 50. But you MUST have some. A slipped timing chain or other cam / valve troubles is the biggest pitfall here, and can also affect SPARK

SPARK....You need a good hot spark and AT THE RIGHT TIME. Slipped timing chains are pretty rare, but on some engines (older Ferds) slipped timing marks on the balancer are not. Once you actually HAVE spark you can check timing on the starter

FUEL.....Good fuel. Make sure not too much. Pull the plugs and inspect. Are they wet, fouled? Dry? don't be afraid to prime a bit of gas right down the carb throats. Use new, "good" fuel.

====================================

With experience, you can forgo some things. EG if the thing "cranks normally" you can get a good idea that it has compression. If it "spins over" or thumps and makes other weird "effects," then it's time to get out the compression gauge / leakdown tester

Checking spark. This should have been fixed "the first day." ISOLATE the problem. SIMPLIFY the problem. Don't worry about side issues until you get the spark FIXED. Check spark right at the coil tower with a grounding probe, which bypasses such things as bad coil wire, bad distributor parts, bad plug wires, or fouled plugs.

Fuel. To repeat, pull the plugs, are they dry or wet. Oil fouled? Hell maybe the needle /seat is stuck open and dumping all sorts of fuel "in there." You have to think

Compression, spark, fuel. Those are the three
 
Getting confused? Have alligator clip leads? Hell you can lay the ignition out on the bench and test it.

You need a coil, the ECU and the distributor

Lay it out on the bench. Follow the diagram. Find the two distributor pickup terminals on the ECU. Hook them to the distributor

Hook the ECU case to battery NEG

Coil does NOT need grounded

Distributor does NOT need grounded.

Hook coil + to the power lead terminal on the ECU. Get a clip lead hooked there and let dangle. This is your battery "hot" when you are ready

Hook something from coil "case" to a probe for testing spark.

Hook up your power clip lead. Twist the distributor shaft while holding the test probe near the coil tower. The thing should make sparks

If not, unhook distributor. Take first one, then the other pickup clip leads, and "tap tap" ground them at the battery connection. Coil should make 1 spark each time you do so.

If not, try another coil. If that does not fix it replace the ECU

IF you hook it all up and it WORKS, then there is something AFU in the car harness. SUSPECT a bad ECU connector OR a bad DISTRIBUTOR connector
 
This is all you need to test the basics of the ignition. You can easily test the ballast separate. A battery, the ECU, distributor and a coil, and of course some test leads

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Below, the basic diagram for a 4 pin ECU

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Below, the wire for testing spark. I use my 12V test light. No, LOL the spark won't blow up the bulb

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Below, the ground connection. ALL you need is one wire from batt NEG to the ECU case

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Below, the two distributor connections. In the car these are polarity sensitive, but for testing does not matter

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Below, the coil NEG connection

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Below, battery PLUS connection, one wire to this terminal of ECU and jumpered over to + side of coil

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Below, all hooked up and ready to test. Should produce sparks at least 3/8" and typically 1/2" long

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Below, distributor "one wire" test. I have removed the other distributor wire for simplicity. Take the bare connector end or this clip lead (the yellow) and with everything hooked up, ground it repeatedly. Each grounding should result in a spark

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Ok guys calm down. I appreciate the help and have no issues trying out the tests you suggest as long as their valid. Here are the pictures I posted about last night.
Current position of the crank. Right at TDC.

Current position of the distributor. Right under the cylinder number 1 terminal like it says too.

you cant see it very much in this picture but the rotor has a little wear on its teeth.


The two videos of me trying to show the coil wire to the distributor to check for spark while starting didn't work when I posted them. But one is about a 1/4" from the block, the other about 1/4" from the fenderwell. Neither of which yielded any arch.


67Dart give me a few and ill put everything out and put it on my bench and run the test like you have it layed out and then post results. If I have enough alligator clips.
 
OK. I cannot get your videos to work. Please don't depend on a test with a factory coil wire. These are usually resistive, might have an open spot inside. Always "start" with a grounding probe.
 
could it be the timing at this point? OP mentions rotor lined up at TDC. Was distributor moved around? Maybe try a timing light on # 1 while cranking, see if you can set timing.
Crank whille jumping, or use a charger with a boost.
 
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