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

[64cudaV8]

Timing wont cause it not to have spark. It just wouldn't start.

 

[SwingerLSX75]

@67Dart. Just finished your bench test. Complete and satisfactory using the methods you described. I also tested it by leaving everything connected and spinning the distributor itself and there were no sparks from the coil using that method.



Also when I did a compression test about 2 weeks ago I had 120 across all 6 cylinders.

 

[SwingerLSX75]

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.

Prior to your suggestion I had only done the resistance checks. But I just did your suggestion with the system setup as it looks above and I saw the bouncing up and down of the millivolts from about 60 to -60 as long as I spun it slow. If spun it fast it only fluctuated between positive 1-3 millivolts.

Since we've kind of narrow it down to the ecu or the pickup and the ecu is the only thing carried locally I may just run down to the store and pick it up and if it doesn't fix it then I can take it right back.

 

[67Dart273]

spinning the distributor itself and there were no sparks from the coil using that method.

may just run down to the store and pick it up and if it doesn't fix it then I can take it right back.

Did you do the "grounding wire" test on the ECU? See the post above I made. If it sparks grounding the one distributor wire, it's not the ECU. Normally auto stores will NOT take back "tried out" electrics.

EDIT Why, in your photo above, does it "appear" that there is a spark present?

 

[nm9stheham]

Per 67Dart273, there is a test of the ECU; I forgot all about that.

You can check the standaed ECU's response to the reluctor by disconnecting the 2 wire harness to the distributor and momentarily grounding one lead to the ECU and then the other while looking for spark. One or the other should produce a spark each time it is grounded/ungrounded. If grounding either of the distibutor pis to the ECU never produces a spark with everything else hooked up, then the ECU is bad for sure.

I think he snapped a photo right when it sparked when disconnecting power to the system.

 

[SwingerLSX75]

Did you do the "grounding wire" test on the ECU? See the post above I made. If it sparks grounding the one distributor wire, it's not the ECU. Normally auto stores will NOT take back "tried out" electrics.

EDIT Why, in your photo above, does it "appear" that there is a spark present?

I haven't done the grounding wire test yet. The picture above I snapped while touching the grounding cable to show that it did in fact fire when grounded like you instructed.

I'm a frequent shopper in the advance near me I used the TRT30 coupon code online a lot to pick things up for 30% for friends when doing work on their cars for them. I can just say they found it while I was on the way to the store and they will take it back. But I'm gonna re read your post and run the test then Ill post the results. If it is the ecu then advance has one and napa has one too.

 

[67Dart273]

At this point I would not be too quick to condemn the ECU. Do the "one wire test" then check the gap in the distributor. You need a .008" BRASS feeler gauge.

You should be able to spin the distributor shaft with a drill and the distributor connector should generate about 1V AC on your meter

 

[SwingerLSX75]

At this point I would not be too quick to condemn the ECU. Do the "one wire test" then check the gap in the distributor. You need a .008" BRASS feeler gauge.

You should be able to spin the distributor shaft with a drill and the distributor connector should generate about 1V AC on your meter

I wasn't automatically saying it was the ecu I just did a quick parts check for what's available in the area.

With the one wire test in your pictures it looks like your jumper from the ecu case to negative battery terminal is disconnected so that's how I set it up to do the test.

Does it matter which one you disconnect? Because with the setup you started with(just like below) I got no spark when grounding it.

But when I switched it to the other post that went to the distributor I got spark each time I grounded it. Mind you both tests were done with the battery negative to ecu case jumper disconnected from the battery.

 

[67Dart273]

Sorry I had it disconnected in the photo. No you want power hooked up, and then ground / unground the indicated distributor terminal

"On a side note," you can also use the Mopar ECU with points, IE convert to a points fired electronic ignition by hooking the points to that terminal. This does not work with the GM HEI, LOL

Make darn sure the ECU is actually grounded

 

[SwingerLSX75]

Well in that case I have no spark or arch or anything with everything hooked up like before with the other distributor cable removed completely and grounding the other distributor terminal jumper to the battery negative. So looks like I have to grab an ecu in the morning and hook it all back up and see what's what. Luckily they are only $22 and I got a few speed perks rewards I can use to save a few bucks to use with a 20% off code that makes it $14.23 picked up in store.

 

[67Dart273]

Very first thing I'd do is double triple check how you have it all hooked up. "Jus because." Hopefully you are finally on the right track

 

[SwingerLSX75]

I looked it over like 3 or 4 times and double checked all the connections. Im going to test it one more time this morning and then go grab the ECU if everything still shows bad.

So i hooked it all back up this morning and it still tested bad. Then I remembered that the PO had given me the original 5 pin ecu in a box and he said he assumed it was bad because he had gotten it from the PO. So I figured that since I had everything hooked up id go ahead and test it for ***** and giggles to make sure it was bad that way I didnt just have 2 bad ecu's laying around.

Well it turns out the original ecu that was sitting in the box in the trunk still works. I hooked it all up lke you described and it passed the original test and teh one wire test. I even took it a step further and hooked it all up the original way and spun the distributor and as the reluctor passed the pickup it fired each time too. So its pretty safe to say the ECU was definitely my problem(fingers crossed). Funny how the original ECU form 1975 still works but one from advance auto parts thats 2 years old has already failed. Im going to throw it back in there and ill grab the other ECU from advance anyway so I have a ready spare. In case this one decides to go seeing as the sappy material out of the back seems to be deteriorated a little bit.
Also going to take some time and clean al the connectors at the firewall and then reconnect since out of all the connections those looks the worst.

 

[nm9stheham]

Make sure you scrape the back side of the mounting flanges on the old ECU to get a good ground to the chassis. Sounds like a plan and a dead ECU would explain the symptoms. You are now on your way to being a Mopar electronic ignition test expert LOL.

 

[SwingerLSX75]

Make sure you scrape the back side of the mounting flanges on the old ECU to get a good ground to the chassis. Sounds like a plan and a dead ECU would explain the symptoms. You are now on your way to being a Mopar electronic ignition test expert LOL.

Thanks to the help you guys gave me Im learning a thing or two about a thing or two when it comes to my first carb vehicle. Should have results after lunch.

 

[SwingerLSX75]

I definitley have spark to the plugs now. But im thinkining i may be 180 out on the crank.
Im going to pull no 1 plug and the distributor and make sure shes on the right stroke the. Drop her down back in and she should be good to go.

UPDATE: Shes running smooth again. Jus checked timing and shes a little off so I have to adjust that but shes good. Id like to thank everyone for their help through everything. I know i may have been confusing or annoying at times, but thanks for sticking with me.
Especially nm9 and once again 67dart helps me out. I appreciate everything.

 

[67Dart273]

You are welcome. Happy you are making progress.

 

[mguner]

Sorry I had it disconnected in the photo. No you want power hooked up, and then ground / unground the indicated distributor terminal

"On a side note," you can also use the Mopar ECU with points, IE convert to a points fired electronic ignition by hooking the points to that terminal. This does not work with the GM HEI, LOL

Make darn sure the ECU is actually grounded

Points controlled electronic ignition..... I see what you are saying but WOW. The points would not burn up since it is a fraction of the current they would normally handle and dwell should be a lot less critical as long as timing is set after the points. This should make the condenser optional as well right?

 

[64cudaV8]

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.

So looks like I was right. You never go to wiring first. You go to removable parts first. Fuses, reisitors caps etc.. Then if all is good you go to wiring not assbackwards. You usually just end up causing yourself more problems than you started with. Glad you found the bad ecu.

 

[67Dart273]

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.

So looks like I was right. You never go to wiring first. You go to removable parts first. Fuses, reisitors caps etc.. Then if all is good you go to wiring not assbackwards. You usually just end up causing yourself more problems than you started with. Glad you found the bad ecu.

You may have been right "this time". ?REALLY? is this how you troubleshoot? You first dive in and replace everything you can replace and THEN find out what was really wrong?


Your strategy is AFU. PROPER strategy tests power, connections AND components to find the actual problem. This could have easily been a wiring problem and often is, and judging from the shape the wiring is in easily could have been

These are not airplanes. These are old Mopars, and they have their share of problems "built in." It's wise to check them out

 

[SwingerLSX75]

I dont think you were right in any case because you never actually gave any helpful information.

I work on 15 million dollar weapon systems when im on sea duty, and i can tell you right now I wouldnt move on in my trouble shooting until fixing the wiring that looked this bad. I hope to god if you come across wiring that looks like this did, whether its an airplane or a go kart you fix it before you move on. I say this mainly because alot of people get in deep to trouble shooting they forget to go back and fix these kinds of things until they cause another problem.

 

[TylerW]

I wish you guys would quit arguing. Pretty soon somebody is going to post up one of those crying kid pictures.

I wasn't mentioned in the thanks but I'll still contribute

The FIRST LAW OF MOPAR IGNITION IS:

Always carry a spare good ECU and a spare good ballast resistor. Always.

You should have checked spark the very first thing instead of going on this wide-ranging, meandering wild-goose chase involving the battery, wiring, ignition switch, voltage drops, etc. Instead of coming in here and asking for opinion after opinion you should have done the very last thing you did, which was try a different ECU.

Anyway, experience is the best teacher and now you know. I'm glad it's running. Don't get out there with an OCD session and get it non-running. Just drive it and enjoy.

 

[adriver]

Wow,
Early last year (I think) I want to tell everyone that I tried TWO off the shelf ECUs from one store trying to get a "new" for the car I keep talking about.
All I had was a handful of used ones.
This particular store was newly opened in town and they didn't "know" me.
So I drove the car up there and showed them a used ECU would work in the car but theirs would not. Got my money back on the second one and went down the street to another store and got a Wells.
It ran and is still running fine.
I posted a thread on it.

Read about my experience two years ago with a used ECU here.
That junk yard orange box lasted for ever.
Till it didn't last anymore.
http://www.forabodiesonly.com/mopar/showthread.php?t=194119

By the way I just noticed that I'm carrying the wrong extra column harness in my go kit.
I wanted to carry one IN CASE my key switch goes bad.
I figure I can just piggy back it on and get going.
But this thread and my recent trouble shooting alerted me.
It has the wrong connector. Must be off something else I scrapped.
(See picture in link above).
I will get the right column harness for the future.

 

[SwingerLSX75]

I wish you guys would quit arguing. Pretty soon somebody is going to post up one of those crying kid pictures.

I wasn't mentioned in the thanks but I'll still contribute

The FIRST LAW OF MOPAR IGNITION IS:

Always carry a spare good ECU and a spare good ballast resistor. Always.

You should have checked spark the very first thing instead of going on this wide-ranging, meandering wild-goose chase involving the battery, wiring, ignition switch, voltage drops, etc. Instead of coming in here and asking for opinion after opinion you should have done the very last thing you did, which was try a different ECU.

Anyway, experience is the best teacher and now you know. I'm glad it's running. Don't get out there with an OCD session and get it non-running. Just drive it and enjoy.

I know i didnt mention you indiviually, but between you and the other two, thats where the most helpful information came from. But 67Dart provided the diagrams and the that led to the faulty part, and nm9 contact me via phone and messages helping the effort along specifically in the right direction.

 

[67Dart273]

You should have checked spark the very first thing instead of going on this wide-ranging, meandering wild-goose chase involving the battery, wiring, ignition switch, voltage drops, etc. Instead of coming in here and asking for opinion after opinion you should have done the very last thing you did, which was try a different ECU.

.

The thing is his wiring IS AFU. And in my experience, a bad ECU has been RARELY the problem in a failed Mopar ignition. In my experience the problems have been

Bad ballast

Bad connections at the distributor pickup

Bad distributor pickup or strike damage on the reluctor (usually worn distributor)

Misc wiring problems usually bad connections AT CONNECTORS

and last.................a bad ECU

Now bear in mind, this is "mostly before" the chineseoisasssssification of replacement parts, so that might bias the results

 

[Killer6]

Congrats youngdart, bet that sounded sweet to the ears when she lit up and
smoothed out! Yeah, once you verified a pulse from the pickup and the wires
from the ign. mod. were OK, you had only two choices. No ground at the mod.
case, or a bad unit. Since you provided the ground switching by tapping coil neg.
to neg. post and she fired, you established that the module wasn't,so it was
either no signal or the above.I have experienced this w/other aftermarket units
as well.67 & mn9s were great with their assistance and providing diagrams etc.
I'm still sending smoke signals & my comp. skills are pretty limited still,one
day......
As far as 64cuda, nanner nanner nanner!! Really dude?Do they have adults
chaperone where you work?And nothing says it would've run w/ the mod. swap
with the poor state the batt. and wiring were in anyhow.I just diaged a bad inj.
harness on an older FWD mopar days ago.Guess I should've just sold them a
set of injectors for $360.00 + labor B4 checking their wiring,huh? In the aviation
world, isn't there an axiom that an aircraft accident is the result of multiple fails?
Just checkin.