2.3 No Spark, Out Of Ideas!!

[Too Fordy]

Hey guys, the end of this build has been frustrating to say the least. The motor is from a 1988 Turbo Coupe and I am having issues getting the coil to fire. Below is a list of things I know
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Coil has 12V
ICM has 12V with key on and start wire has 12V when cranking
Coil voltage drops to 6 or 7 when cranking... which is weird.
The distributor spins
The distributor is brand new, so is the module
I have a known working module from a working car and it makes no difference
Test light is showing zero spark from the coil while cranking
The spout and pip wires go to their proper locations and seem to be undamaged
I can sometimes get the coil to spark once by rotating the distributor by hand
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What is bugging me is the voltage drop at the coil during cranking. I am thinking that 7 volts is not enough to fire the coil. I have no idea why its dropping that low during cranking.

 

[a91what]

The coil should get a constant 12v on one side and the other is grounded to fire the coil. I would take readings across the coil windings to see if there is a issue on the coil itself. You may have a wiring issue or a severe voltage drop issue (usually bad grounds) on the battery/start circuit.

 

[Too Fordy]

The coil should get a constant 12v on one side and the other is grounded to fire the coil. I would take readings across the coil windings to see if there is a issue on the coil itself. You may have a wiring issue or a severe voltage drop issue (usually bad grounds) on the battery/start circuit.

The coil is brand new... I actually have 2 brand new coils because I thought I lost the first one. The ground thing seems interesting. My battery is in the back. The neg terminal of the battery is bolted to the frame, the starter is also grounded to the frame. Is this not enough? Should I ground the engine itself to the frame?

 

[a91what]

No you need to run a ground all the way up to the engine block. I had to just to get my car to turn over, this is with two batteries in the trunk.

 

[Red_LX]

Sooo, might not be any help but when I first built the engine for my Turbo Coupe it would crank but not fire.

I had used a distributor that had been in the engine I rebuilt, so I pulled the distributor off my old engine and it was fine. I don't know if it was the TFI module or what, but if you have access to another distributor it might be worth a try.