No spark on only 2 dizzy cap points?

[dweinhart]

I am confused. New coils,new caps, new wires but I have intermittant spark loss on just 1 side of my distributor cap... How is that possible>

 

[dweinhart]

What can cause a spark loss on only 1 side of dizzy? I have swapped caps to other side in case my new caps were bad but the the spark loss stays on same side. Can someone tell me where signal comes from for the spark?

 

[ivan129]

I'd be chasing the source backwards from the distributor that has not spark, HT lead, coil, wiring to the coil, power and trigger signal at the coil. If no signal, wiring from ECU, cam angle sensor. Not hard to do if you you have one working side to compare with. Just need a volt meter and test lamp. You could start by removing the HT lead from the bad dizzy's coil and fit a spark plug lead to the coil, run the lead to a spark plug earthed against the metal body of the engine, crank and check for spark. Good luck.

 

[Zuffen]

I'd swap trhe igniter plugs over and see if the fault swapped distributor caps.

That will tell you if they are working.

If they are the problem is between them and the coils or after the coils.

If the problem swaps distributors you could have a dead igniter of a wiring issue back to the ECU.

 

[dweinhart]

I'd swap trhe igniter plugs over and see if the fault swapped distributor caps.

That will tell you if they are working.

If they are the problem is between them and the coils or after the coils.

If the problem swaps distributors you could have a dead igniter of a wiring issue back to the ECU.

Ended up being Crank Position Senor not on correctly. And I found my new NGK wires had been installed by mechanic without base underneath them at the Cams and they were chewed through. Replaced wires and problem went away for awhile but now its back

 

[Zuffen]

I know it sounds like a lot of work but you could buy the engine loom and ECU from an LS400 (out of the same car) and fit them to your engine. Personally that would be my course of action.

This would only leave the body plug to sort out.

 

[dweinhart]

After replacing all this..still had problems. I finally opened the ECU and found burnt ribbon wiring was the culprit