No Spark

[furyfever]

Just wondering if anyone can give me some advice on how to fix my buddies car. He's got a 66 Dodge Coronet convertible with a 318 poly and electronic ignition. It turns over but won't start (have tried a shot of starting fluid). He replaced the coil last fall but that didn't fix problem. Now this spring, I've been over there twice and have determined that he's not getting spark. I removed the number two plug and grounded the end while he turned it over. No spark. What would be the best way to proceed now? I thought to remove electronic ignition and put the points and condenser back in but unfortunately, he didn't save the old parts. He said he made the upgrade about 6 years ago. Thank you, Bob

 

[traintech55]

You did not say in your OP that this is a Chrysler electronic system or not, so I will assume it is.
1. Remove distributor cap, have someone crank the engine, and verify the distributor is turning, (You would be surprised how many times this is overlooked). If turning proceed to step 2.
2. Use a test light, or multi-meter and verify voltage on the positive side of the coil with the key in the on position, It not, crank the engine and verify voltage. (If off in the run position, but on in start you have a bad ballast resistor or ignition switch).
3. If good to this point, lay you hand on any Chrysler electronic distributor, and plug the pickup into the harness. Rotate the other distributor by hand. (If you have spark now you have a bad pickup coil, or bad air gap in the distributor).
4. If everything checks out it is probably a bad control module, make sure your old one has a very good, clean ground before you replace it.
Keep us posted.

 

[Big_John]

You did not say in your OP that this is a Chrysler electronic system or not, so I will assume it is.
1. Remove distributor cap, have someone crank the engine, and verify the distributor is turning, (You would be surprised how many times this is overlooked). If turning proceed to step 2.
2. Use a test light, or multi-meter and verify voltage on the positive side of the coil with the key in the on position, It not, crank the engine and verify voltage. (If off in the run position, but on in start you have a bad ballast resistor or ignition switch).
3. If good to this point, lay you hand on any Chrysler electronic distributor, and plug the pickup into the harness. Rotate the other distributor by hand. (If you have spark now you have a bad pickup coil, or bad air gap in the distributor).
4. If everything checks out it is probably a bad control module, make sure your old one has a very good, clean ground before you replace it.
Keep us posted.

As an alternative to #3, if you don't have an extra distributor, you can check the distributor with a DMM and a feeler gauge. First, check the gap with a brass feeler gauge. It should be .008" between the pickup and the reluctor. Unplug the distributor and check the resistance between the two distributor connections. It should be around 800-1500 ohms. That verifies the pickup coil is OK. Now, leave the probes in the connections, switch the DMM to AC voltage (yes, AC voltage) and crank the engine over. You should get a voltage reading greater than 1 volt.

 

[CBODY67]

I guess you've swapped the coil-to-distributor cap wire for a known good one?

 

[furyfever]

Great...you guys have given me plenty to check the next time I go over there. I think I understand everything you (all) are saying. It is a Mopar electronic ignition. Reason I know: there's an orange module mounted on the firewall with a Mopar part number on it. I do not have a known good spare electronic pickup or module, so Big_John's alternative to #3 should prove useful. Thank you all...I'll keep you posted. Also, It's GOOD on all of you to help me help my buddy. He recently had a very serious surgery due esophogeal cancer. He's still on the mend and really appreciates the help! TY and God bless you all for your help.

Bob

 

[commando1]

You are a Saint, John.

 

[traintech55]

As an alternative to #3, if you don't have an extra distributor, you can check the distributor with a DMM and a feeler gauge. First, check the gap with a brass feeler gauge. It should be .008" between the pickup and the reluctor. Unplug the distributor and check the resistance between the two distributor connections. It should be around 800-1500 ohms. That verifies the pickup coil is OK. Now, leave the probes in the connections, switch the DMM to AC voltage (yes, AC voltage) and crank the engine over. You should get a voltage reading greater than 1 volt.

Forgot about this one John. (It has been so many years since I did that test. Ooops).

 

[furyfever]

Was able to get over my buddies today and make some measurements.

1. coil to distributor wire ok. Resistance was very low...lower than the wire on my own 68 Fury.
2. removed distributor cap and rotor turns when cranking engine.
3. positive side of coil when key is in run position = 5.93 volts
4. positive side of coil when key is in start (cranking) position = 8.1 volts
5. air gap of pickup to reluctor is .008 -.009"
6. pickup resistance = 277.8 ohm
Here's Big Johns alternative to #3 "Now, leave the probes in the connections, switch the DMM to AC voltage (yes, AC voltage) and crank the engine over. You should get a voltage reading greater than 1 volt."
7. pickup side = .219 vac
and made an extra measurement too....
8. module side = 0.0 vac

So is it (for sure) a bad pickup?

TY, Bob

 

[Big_John]

Was able to get over my buddies today and make some measurements.

1. coil to distributor wire ok. Resistance was very low...lower than the wire on my own 68 Fury.
2. removed distributor cap and rotor turns when cranking engine.
3. positive side of coil when key is in run position = 5.93 volts
4. positive side of coil when key is in start (cranking) position = 8.1 volts
5. air gap of pickup to reluctor is .008 -.009"
6. pickup resistance = 277.8 ohm
Here's Big Johns alternative to #3 "Now, leave the probes in the connections, switch the DMM to AC voltage (yes, AC voltage) and crank the engine over. You should get a voltage reading greater than 1 volt."
7. pickup side = .219 vac
and made an extra measurement too....
8. module side = 0.0 vac

So is it (for sure) a bad pickup?

TY, Bob

I don't know if it is "for sure" a pickup or not, but those readings don't look good to me. Usually, the pickup is open or has excessive resistance, so it makes me wonder a little.

@traintech55 Whatchothink?

 

[traintech55]

I don't know if it is "for sure" a pickup or not, but those readings don't look good to me. Usually, the pickup is open or has excessive resistance, so it makes me wonder a little.

@traintech55 Whatchothink?

God how I love it when someone asks what I think. OK, first I do do like the D/C voltage readings at the coil, check the voltage across the battery, if it is not up to 13 volts, charge it up, and then take the readings again. If the engine is cranking to slow, it will throw everything off.
If you have 13 volts at the battery, check through the system as to why it is so low at the coil.
If you charge the battery up, and still have the same problem, get a reman from the parts store and plug it in, and test for spark. As long as the part is not installed you can return it, and if it works, you needed it anyway.

 

[Big_John]

If you have 13 volts at the battery, check through the system as to why it is so low at the coil.

Could that ~8 volts at "start" be because of the dual ballast resistor?

If it does have a dual ballast resistor, I think a check of voltage before and after the ballast resistor in "start" could tell us something.

 

[traintech55]

I am hoping when it was converted, they used the Chrysler kit. Since all the new control modules are four pin, not five like the originals, it should not have needed the dual ballast resistor. We may need some pictures to get to the bottom of this.

 

[furyfever]

Thanks guys for your quick responses. I dont have photobucket anymore...What's the easy alternative to posting photos now-a-days? I've been meaning to figure this out ever since photobucket kicked the bucket. Anyways, like I said before there's an orange box on the firewall with a mopar part number right next to the ballast resistor and another small box too (has a chrome finish). In a few days I'll get some photos and figure out how to get them on here. TY again

Bob

Edit: Forgot to tell you guys that he bought a brand new battery just a few days ago. These measurements were taken with it in place/cranking with it. Next time I go over there though I'll make measurements again with a battery reading too. TY

 

[marty koirtyohann]

Just wondering if anyone can give me some advice on how to fix my buddies car. He's got a 66 Dodge Coronet convertible with a 318 poly and electronic ignition. It turns over but won't start (have tried a shot of starting fluid). He replaced the coil last fall but that didn't fix problem. Now this spring, I've been over there twice and have determined that he's not getting spark. I removed the number two plug and grounded the end while he turned it over. No spark. What would be the best way to proceed now? I thought to remove electronic ignition and put the points and condenser back in but unfortunately, he didn't save the old parts. He said he made the upgrade about 6 years ago. Thank you, Bob

question I dont think anyone asked? did it ever run with this set up? was a new set up as in new in the box or a swap meet buy? if it never ran r u sure its wired right? or the componets r good . do the basic electronics check like every one said heee , do a prosess of elimtion. check the wiring to make sure its is wired right ,if that checks then like the one guy check to make sure u have
volts @ the coil use a volt-ohm meter . if u have voltage there then check the pick up coil also check the ballast resistor (the pin boxes have ballast the pin had (side by side) after u have passed all the checks & it passes then the only thing lef is a bad control box

 

[traintech55]

No problem, we have a number of good guys on this site, and most of us have been down this road before. I did not know you had installed a new battery, but make sure it is not discharged due to to the constant cranking.
If the battery is charged, use your multi meter and follow the red wire into the car. it should go to the top stud on the starter relay, then through the bulkhead connector to the input side of the ammeter gauge. From the output side of the gauge to the main dash spice in the harness. them it goes to the alternator top stud, and the fuse box, (constant hot side), and the input to the ignition switch. It then comes out of the switch (Blue wire) to the input of the ballast resistor, coil, and voltage regulator,
(All these wires pass through the bulkhead connector also). On an almost 60 year old car these wires can have a lot of corrosion restricting the current flow.
Now you stated that you have an orange control module, if my memory serves me correctly this is a race only box. Remove the plug from the module and count the pins, the new style modules have four pins, the old ones have five, (This is the reason for the dual ballast resistor). You should have four wires you need to worry about, the orange and black wires are from the pickup module in the distributor. the gray wire, (or black with yellow strip) should go to the negative side of the coil, and the blue wire should be the voltage input to the control module. You should have 12 volts on this wire with the ignition switch on, or start. check these out and keep us posted.

 

[70bigblockdodge]

If the battery is up, it is losing voltage somewhere.

 

[rags]

agree with above. low by three volts. could just run a hot wire to the coil. crank it and check for spark. would at least confirm the ignition components are good, then just back trace the low voltage.

 

[John Kirby]

I would try swapping the ends on the ballast resistor and measure the coil voltage again. The resistors are not the same value and it's worth a try. You definitely have a low voltage issue.
Another thing, disconnect the starter relay trigger wire while measuring the coil voltage. This will stop the engine from cranking and dragging down the voltage. Have someone turn the key to start and measure the coil voltage (+ side) it should be ~12-14V if your battery is good. If not you have a bad connection somewhere. The ballast should have very close to battery voltage on one of the wires when the key is in the on position (not start). It normally is the blue wire. IGN1 in these diagrams.

Here's a couple wiring diagrams. It doesn't matter what the box color is, they are all wired the same. It is possible the voltage regulator or alternator is bad and pulling down the voltage. Try disconnecting them temporarily and see if the voltage is correct. A likely culprit is the bulkhead connector is corroded if nothing else fixes the low voltage issue. Looking at your results you said #8, 0 volts when turning the distributor and measuring the pickup coil voltage at the control box. You had 0.219 VAC at the distributor connection and should have the same at the box connector when it's disconnected and probed with the meter. That doesn't seem right. You need to verify that.

 

[furyfever]

The new battery that we installed, did crank a bit slow at first. We slow charged the battery for a day/night and then I made the measurements I recently posted. Cranking was noticeably faster after charging. After cranking it a bit more the other day to get those measurements, I again put it on the charger so I know the new battery will be where it should be the next time I go over. I'm careful with that/realize if a battery is low it'll have poor spark. I was surprised I was only getting 8 volts on coil when cranking the other day...thought to myself where's the other 4 volts?

Yes, car ran with this setup up until last fall. Owner stated that the electronic ignition was put it about 6 years ago. Owner installed a new coil last fall after car wouldn't start...(was just guessing that this was the problem) He stored it for the winter/had his surgery...asked me If I could come over this spring to see what problem was. Battery was bad first time I went over....He got a new one...that's where we're at now.

You guys have given me a lot to read and think about (even though I don't understand it all). I think it'll make more sense though after reading all the posts a few more times and poking around under the hood a bit more. I'll keep you posted, Thanks again...everyone.

Bob

 

[Big_John]

Here's some reading on the Mopar electronic ignition.

Chrysler Electronic Ignition System