weak spark & won't start

[Tscott38]

Need help with a 68 440 w/ electronic ignition - a restoration/project car I've been slowing working on.  Lately I've been restoring the cluster and interior, and since i'm not a good mechanic, i start the car every day to make sure i haven't messed up anything as I've got wires everywhere.  - the original harness is in good condition.  It has always started and ran fine.  This has been going on for months.  I even drove it a little - ran great. 

One day I decided to put the cluster back in, by the way I put a new exhaust system on it too(which required that I partially drop the starter).  Once I got everything together, tried to start and - no spark.  Took a plug out in the dark and realized there is a faint yellow orange glow coming from one of the the plug when I grounded the plug on the exhaust manifold or alternator housing.  I guess i have a very weak spark, and I guess this is the reason it won't start.  Its getting plenty of fuel. 

My multimeter doesnt seem to be working anymore right now so I can't say anything about voltages.  I know my battery is old, but it cranks the engine over OK.

Where shoudl I start?  I find it hard to believe the ECU or coil went out the day I put the cluster in.  Could I have done something in the wiring?  Could my messing with the starter have caused anything?

Thanks for any assistance.  I'm at a loss.

[b5blue]

Check groundings all over under the hood and check ignition connections at the dash. Check bulkhead connections. You really need a great battery not a weak one! These cars suffer from weak battery and poor connections as stock alt. idle output amps are low to begin with. A meter is about 10-12 bucks a Wallymart, get one!

[Tscott38]

I checked my ecu - it was rusty where it was connnected to the fenderwell, cleaned that all up so its nice and shiny - still no luck - same hard to see spark.   I will get another battery next week probably, but since it cranks the engine over OK I thought I may be ok.  As for ignition connections at dash - all i did was tie the two alternator wires together (I removed the cluster again in hopes of reversing steps that got me into this mess) and left the rest loose.  Seemed to work like that before. 

Does the ignition switch have to be grounded?   

[dodgechar]

  May check juice at starter relay before stater, than at stater.  could be starter relay on firewall.  Also you may try grounding the dash cluster better.  I sanded the  points on the dash  were the cluster meets at the studs and added a wire to the body  sanded to the metal and bolted on from one of the studs.  If nothing else it may make you dash lights respond better to the  dimmer roller. Have the battery checked at parts store of you choice. Used msd 6a on mine,  works great. Wires to distributer easy and provides plenty good fire. Also bypassed the ammeter but thats another project. 

[b5blue]

Weak battery.....when cranking you have little juice left for ignition system. 

[slash19]

Weak battery.....when cranking you have little juice left for ignition system. 

My 68 charger wants to die when put in reverse and at regular idle when put in drive also.

[Tscott38]

Got it to fire.  Still have the weak orange spark though, so I misdiagnosed the problem - I said I wasn't a good mechanic in the beginning.  Apparently I flooded it and after a few days went out, the carb bowls were dry, shot some starting fluid in there and - fired right up. 

Now, the weak spark issue - where should I look first - coil - ballast?  I believe I have a 1.5 ohm ballast and a stock coil.  I want to retain a stock appearance, so no accel super coils please. Any suggestions?

The batery is old but I charged it up and is showing a "good" on a hydrometer - should I really be concerned that it isn't up to par?   

Thanks for the help. 

[b5blue]

FBO...
   www.4secondsflat.com   Have Don set up a dist. to your motor, you won't regret it.
                                         Get "Firecore" plug wires from firefighter (Ron) he's a member here. Use NGK XR-5 plugs.

[W4ATL]

I have had issues with 2 coils on my Charger so they can go bad. A new coil is a cheap thing to try. Then new spark plug wires and then spark plugs.  Besides the distributor pickup that should be everything in the circuit.  The Firecore wires are good. I got some custom made to length since the ones from the auto store weren't long enough for my application.

Keep us posted. 

[maxwellwedge]

Got it to fire.  Still have the weak orange spark though, so I misdiagnosed the problem - I said I wasn't a good mechanic in the beginning.  Apparently I flooded it and after a few days went out, the carb bowls were dry, shot some starting fluid in there and - fired right up. 

Careful with that starting fluid - It can bust your engine open.

Always squirt some gas instead.

[Tscott38]

thanks for all the suggestions - they are appreciated.  I'm awful slow with this car, but I've got more time than money anyway. 

[Tscott38]

After having problems with no spark and weak spark, I finally got the car to fire, but I had already removed the gauge cluster when it did fire.  After putting the cluster back in, I returned to the same problem - no spark.  After replacing the ECU, coil and ballast, still same problem. 

I then removed the cluster.  It fired right up again.  So, what gives?  The ammeter seemed to work when I had the cluster in and when  had it out, i just tied the 2 wires together.  i had the cluster screwed in to the dash good and tight and the ignition switch is also nice and tight.  What other wires that go to the cluster could be causing  a no spark situation???

[dodgechar]

  If you bypassed the ampmeter when the car stated and had the dash out  you got more juice to system.  When you put the dash back in  you connected the ampmeter you went back to the old lack of juice.  I'd  buy a new battery , eliminate the bad battery question and move on.   The whole system is outdated in more ways  then one.  I  believe if you go to madelectronics.com.   Look for amp bypass, you'll see what mean.     

[Tscott38]

the battery is new.  The ammeter is orignal though. 

[dodgechar]

  If you have dash out and the two  ampmeter wires screwed  together and taped  then put the dash in.  Will it start?   That would bypass the amp.  IF you have the dash out but connect the ampmeter and try to start.  What happens?  Point being the ampmeter is a flaw in this system.  I'm glad you got a new battery, step in the right directions.  Check that madelectronics site.  IT has some helpfull stuff in the tech area.

[b5blue]

  The wires that attach to the AMP gauge, just put them together as described above for now. Make certain your battery is fully charged and recheck all connections, ground straps, fuses, connectors. Try to get back to "ran fine" condition, even if gauge set is out. You may just have a slight flooding problem with the carb. making you think weak spark.    Your spark at start or cranking is totally dependent on the condition of your battery's state of charge along with how good the rest of your ignition system is.

[70 Charger RT]

I've heard that mopar starters draw high current and thus not allowing full voltage for some electronic ignition systems.  I picked up a mini starter from 440 Source.  I'm hoping this will help reduce current draw and thus voltage drop to the ignition.

[b5blue]

If your cigarette lighter socket is hooked up and works you can make an adapter out of any 12 volt accessory plug in (For the lighter socket.) to hook a meter to. That will let you read whats going on while cranking. (And hopefully running!) 

[Tscott38]

SOlved my problem with the helpf of this board and thought I'd post the result.  The issue was that it had spark with the cluster out and did not when the cluster was in.  The wires that connect to the tic toch tach and to the clock are very similar and I had them switched.  It caused the wires to ground out somewhere and killed most of the sprk to the coil.  Switched them back and it fired right up withth ecluster in. Thanks to all who contributed.

[elacruze]

SOlved my problem with the helpf of this board and thought I'd post the result.  The issue was that it had spark with the cluster out and did not when the cluster was in.  The wires that connect to the tic toch tach and to the clock are very similar and I had them switched.  It caused the wires to ground out somewhere and killed most of the sprk to the coil.  Switched them back and it fired right up withth ecluster in. Thanks to all who contributed.

BEEN THERE!

Glad you found it. Glad the solution presented before I read it-gotta love how this forum gets your head in the game sometimes.

[b5blue]