79 x1/9 No spark

F

Fiatfanatic21

Low Mileage
I bought the car last summer, trailered it home and gave it a light wash before pushing it into the garage. The car ran pior to a washing it by squirting gas in the carb because the fuel pump is questionable and fuel tank most likely leaks.

Then… No spark.
Ok well, water must of shorted something out, no problem.

Months later here we are with new:
OE Distributor from ebay and cap from bayless
OE Control module from bayless
OE Coil pack also from bayless
And still no spark!
Continuity tests on ALL wires in the ignition system and it’s all good.
12v to resistor 8v out.

Coil does work (by connecting a spark plug directly to the coil instead of the cap, grounding the plug, attaching a jumping wire to the the (-) terminal and grounding that out to mimic breaker points) we get spark.

But no spark. My father and I are at witts end. Please help.

Andrew-
 

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Im good on my teeth. When I take a spark plug out and ground it out on the engine block, no spark.

Added an extra ground wire for the engine make that it’s grounded well to.
 
Fiatfanatic21 said:
by connecting a spark plug directly to the coil instead of the cap, grounding the plug, attaching a jumping wire to the the (-) terminal and grounding that out to mimic breaker points) we get spark.
Click to expand...
What happens if you don't ground the (-) wire and let the distributor make and break the connection?
 
Ignition timing is set up correctly? Pointing at terminal 4 on the cap with 1 and 4 at TDC and valves on overlap on cylinder 1?
 
Have you checked for spark with an in line light? Just to be clear, this is a later year system without points? Sounds like the distributor could be the culprit. How does the rotor look?
 

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Dumb question - How do you know "no spark"? Everything hooked up, take one plug out, ground it and crank and observe spark [or no spark] in gap? Rinse and repeat for several plugs?
 
FiatFunk said:
Ignition timing is set up correctly? Pointing at terminal 4 on the cap with 1 and 4 at TDC and valves on overlap on cylinder
Click to expand...
Isn’t TDC for the fiat the top of compression stroke on cylinder 1? I made sure to do that before taking out the the distributor and took some pictures to be sure it’s oriented the same way when I replaced it.
But suppose im off a tooth when I changed it out. Wouldn’t I still be getting spark, just at the wrong time?
I don’t get any juice going to the cap unless I simulate breaker points at my coil, only then will my coil send spark to the cap.
 
Fiatfanatic21 said:
Isn’t TDC for the fiat the top of compression stroke on cylinder 1? I made sure to do that before taking out the the distributor and took some pictures to be sure it’s oriented the same way when I replaced it.
But suppose im off a tooth when I changed it out. Wouldn’t I still be getting spark, just at the wrong time?
I don’t get any juice going to the cap unless I simulate breaker points at my coil, only then will my coil send spark to the cap.
Click to expand...
Ignition timing is done on 4, both valves closed on 4, intake opening on 1.
But yes you should still be getting spark at the plugs just at the wrong time.
Is your control module grounded?
 
Fiatfanatic21 said:
Coil does work (by connecting a spark plug directly to the coil instead of the cap, grounding the plug, attaching a jumping wire to the the (-) terminal and grounding that out to mimic breaker points) we get spark.
Click to expand...
To confirm...

There is a spark when the ignition power is on, starter run followed by a spark at the spark plug hanging by the HV coil wire with the shell of the spark plug grounded?

~But no spark at the distributor connection wires going to each individual cylinder?

~If yes, check the rotor for connection. stock oem Bosch rotors have a resistor inside that can fail open/no connection.
~Check the carbon rotor contact inside the center of the distributor cap.
~Right angle Bosch caps are known to develop internal open/shorts causing a mis-fire to no spark at a pair of cylinder connections.
~Check the ignition wires to each cylinder.

Check/verify the apparently simple/obvious items that is "believed" to never have a problem or is "new" for failures. Keep in mind new does not mean assured functional, functionality must be verified by testing.


Bernice
 
Rupunzell said:
To confirm...

There is a spark when the ignition power is on, starter run followed by a spark at the spark plug hanging by the HV coil wire with the shell of the spark plug grounded?

~But no spark at the distributor connection wires going to each individual cylinder?

~If yes, check the rotor for connection. stock oem Bosch rotors have a resistor inside that can fail open/no connection.
~Check the carbon rotor contact inside the center of the distributor cap.
~Right angle Bosch caps are known to develop internal open/shorts causing a mis-fire to no spark at a pair of cylinder connections.
~Check the ignition wires to each cylinder.

Check/verify the apparently simple/obvious items that is "believed" to never have a problem or is "new" for failures. Keep in mind new does not mean assured functional, functionality must be verified by testing.


Bernice
Click to expand...
Yes kind of. If I just hook a plug straight to the the coil and crank it over I won’t get spark, only If I break the connection at the coil on the negative terminal will I get spark to come out of the coil.

It’s like my control module isn’t doing its job. I it got from midwest bayless, not entirely impossible for it also to be malfunctioning.

Is it possible to do a simple continuity test on my rotor? I know some of those types of wires don’t really work for continuity test like the spark plugs wires. I’ve been able to test the plug wires by using them on my dads vac case tractor.
 
Fiatfanatic21 said:
Yes kind of. If I just hook a plug straight to the the coil and crank it over I won’t get spark, only If I break the connection at the coil on the negative terminal will I get spark to come out of the coil.

It’s like my control module isn’t doing its job. I it got from midwest bayless, not entirely impossible for it also to be malfunctioning.

Is it possible to do a simple continuity test on my rotor? I know some of those types of wires don’t really work for continuity test like the spark plugs wires. I’ve been able to test the plug wires by using them on my dads vac case tractor.
Click to expand...
Sounds like your coil is fine as the test you did simulating a set of points produced spark.

Some issues to investigate could be the distributor failing to send a signal to fire the control module, the cable between the distributor and control module not transmitting the signal, a problem with the control module input or output, or some combination of them all. In the 79 - 82 Fiat service manual (available for download in the Wiki section) there are procedures for checking the electronic ignition including the distributor, control module, and coil (page 55-7).
 
Fiatfanatic21 said:
Yes kind of. If I just hook a plug straight to the the coil and crank it over I won’t get spark, only If I break the connection at the coil on the negative terminal will I get spark to come out of the coil.

It’s like my control module isn’t doing its job. I it got from midwest bayless, not entirely impossible for it also to be malfunctioning.

Is it possible to do a simple continuity test on my rotor? I know some of those types of wires don’t really work for continuity test like the spark plugs wires. I’ve been able to test the plug wires by using them on my dads vac case tractor.
Click to expand...
Start at the four rotor/stator arms inside the distributor. If any of them are bent out of spec (think spec is about 1mm gap, check this) or touching, there will be no trigger signal to the EI box. If this rotor to stator gap is verified ok,

Put an ohm meter on the sense coil connections to verify connection to the coil. These have been known to fail. Bosch had termination problems with their early version of this coil that can fail by broken wire. Bosch revised how the coil wires were connected to the terminals which resolved the broken connection problem.

Verify the ALL wiring/connections to the EI box IS good.

If all those checks are verified good, try another EI box that is verified as working/functional. Those Bosch EI boxes are pretty reliable until they get soaked in water. This happens due to the location of the EI box. The side compartment has a drain at the bottom which almost always gets clogged with leaves, dirt and etc. The drain plugs up, with the first car wash or rain that compartment fills up with water drowning the Bosch EI box. Often not noticed due to the black plastic covers.. In short time water soaks into the Bosch EI box drowning the EI box to a slow death.

Pointless to check the rotor and other parts of the HV system if the EI box/distributor cannot be verified as working. It's one item, one part of the system checked-verified functional before other parts of the system can be tested-checked.


Bernice
 
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