Ign. spark

[seitz]

i have a 340 electronic ign with a new ECU i only have spark at the coil when key turns off. Coil and Ballist test fine with volt meter have power atboth sides of ballist
i have ordered new coil and ballist but i dont think that is issue anyone else have same prob

 

[halifaxhops]

Check for power at the ballast at start and run. should be at least 12vdc going in. sounds like the ballast is fine, Kind of sounds like a bad connection somewhere. Remember voltage can be going through a strand of wire and no real amperage or a bad connection that wont handle the load, it is usually 4 amps not running and 2-3 running. Load light is your friend here. If every thing is good then you have to trouble shoot the ign system. New does not mean good in todays electronics. Lots of bad "fake" ecu's out there. Did it ever run with the new one?

 

[Dave999]

By the sound of things
it sparks in run but won't spark in start
coil shouldn't be powered in the ACCessory position or in off position
coil had power at some point otherwise it can't produce a spark
but it doesn't start..so its not sparking in start.. thats my thinking

its a guess...as usual but

if it was a problem in RUN position the car would start in START position and die when you let the key click back to RUN position

problem could be anything...from bad igntion switch to poor connection at the switch or bulkhead to bad connection on ballast or ECU

but then again as HH says above could also be a bad ignition module or a bad trigger in the dizzy

spark is produced when there is a rapid loss of power to coil
that rapid loss can be triggred by the module as the motor turns over or by you action at the key

if it sparks
from RUN to START on the key
and
from RUN to ACC or OFF on the key
power feed when key is in start is the problem.

In general you have 4 wires to igntion key switch 12 volt in, acc out, run out, and start out... check the connector block isn't corroded.

start investigation with the things that cost nothing but time to do.

This is the exact issue you get if the wires from the ignition switch are swapped over in a mix up. i can't remeber which 2 you have to swap but the "power feed" and the start wire or the run and start wires swapped gives very odd behaviour.

having had to nut-out a car with 4 red wires to the switch 24 ways you can configure that connector, what kind of sick individual does that!!!!. You can conspire to create exactly the symptom you have with one of those 24 different and wrong ways to connect...

Dave

 

[Dave999]

one other thing...
is the 12 volt feed from the starter relay or back of starter solenoid to the coil end of the ballast connected? i.e the 12 volts for START that switches off in RUN for car equipped with a ballast and 8 volt standard coil?

and is your battery low
or are you running a mini starter without provision for the extra wire?
might be as simple as only 6 volts or so at the coil while starter motor is turning...

 

[seitz]

By the sound of things
it sparks in run but won't spark in start
coil shouldn't be powered in the ACCessory position or in off position
coil had power at some point otherwise it can't produce a spark
but it doesn't start..so its not sparking in start.. thats my thinking

its a guess...as usual but

if it was a problem in RUN position the car would start in START position and die when you let the key click back to RUN position

problem could be anything...from bad igntion switch to poor connection at the switch or bulkhead to bad connection on ballast or ECU

but then again as HH says above could also be a bad ignition module or a bad trigger in the dizzy

spark is produced when there is a rapid loss of power to coil
that rapid loss can be triggred by the module as the motor turns over or by you action at the key

if it sparks
from RUN to START on the key
and
from RUN to ACC or OFF on the key
power feed when key is in start is the problem.

In general you have 4 wires to igntion key switch 12 volt in, acc out, run out, and start out... check the connector block isn't corroded.

start investigation with the things that cost nothing but time to do.

This is the exact issue you get if the wires from the ignition switch are swapped over in a mix up. i can't remeber which 2 you have to swap but the "power feed" and the start wire or the run and start wires swapped gives very odd behaviour.

having had to nut-out a car with 4 red wires to the switch 24 ways you can configure that connector, what kind of sick individual does that!!!!. You can conspire to create exactly the symptom you have with one of those 24 different and wrong ways to connect...

Dave

Thanks everyone i am gona go back at it tomorrow will install new ballist as well as coil if that dont work all follow some wires everything is new harness included car turns over at key i have power at ECU as well as both sides of ballist also Dizzy is fine which should not effect spark at coil. i have never had the car started with the new parts. I will let ya know what i come up with

 

[Dave999]

well if its all new

have you got the dizzy 180* out ie at TDC has the rotor perfectly aligned with plug wire 1 but back to front i.e its tail is aligned with plug wire 1 not the tip..... its so easy to do... i.e you are sparking the cylinder that is no.1s partner when you should be sparking no.1

rotate engine to TDC mark pull dizzy, put back in with rotor exactly opposite way and see if you have success.

it will start at least, with anything from 0 to 15 * BTDC provided you are not 180* out at the dizzy.

 

[seitz]

dizzy is good iam trying to get spark at the coil. I installed another new coil and ballist still same only spark at coil when key goes into off position i have power at both sides of ballist when key is in on position. pow er at both sides of coil wh en key turns t start. I have power at ecu plug when key is in on position and the other terminal powers up when key goes to start. i dont have power coming out of the two dizzy terminals at ecu. I have another new ECU coming but i dont think this is the issue. because i shoudl still have spark at at coil. i the ignition is new and car turns over all wire power up like they should when key is in start position. Very confused!!!!!! to note should there be power to both side of the ballist when key is in on postion? or one side then they other when key goes to start position? also i tested the ECU with a volt meter and teh dizzy terminals test good even more confusing to me . What am i missing??

 

[halifaxhops]

Try to help here the pickup in the distributor will not get power it produces a very small ac signal that the ecu amplifies and tells the coil to fire. Now if that is open or shorted it will not fire the coil. I would hit the plug going into the distributor and see how manty ohms is between them NOT to a ground. #2 Yes the ballast has two sides one side is run the other is start. This might help.

 

[seitz]

ok maybe iam going about this wrong i do have this diagram i have a 2 pole ballist but same same idea as the 4 all replace the ecu once again and see what i have for ohms at dist

 

[seitz]

Thanks everyone for the help. It ended up being the gap on the Dist pickup was to big. Last think i checked. I new it was somthing simple but that was not what i expected i replaced it a while ago and i must have got side tracked and not set up the gap when i rebuilt the dist.

Next issue i have is in my instrument cluster its a duster 70 ralley dash. The exterior lights all work including signals. Also the dash breaklight works inter works also. What i dont have is the signals in cluster as well as the dash lights when head lights are on. I have the map lights that work and dim with dimmer switch. I have tested all the bulbs and sockets as well as the board on teh back of the cluster and everything tests fine with multi meter. I have all the grounds at column and engine and rad support. any ideas what could be the issue with the dash lights? i can only think of ground. I also have tested the plug in the harness that plugs into back of cluster and the signal wire has power going into cluster. Frustrating also. again i and sure iam over looking somthing simple. Thanks In Advance