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2.3 No Spark, Out Of Ideas!!

  • Thread starter Thread starter Too Fordy
  • Start date Start date Jul 14, 2017
T

Too Fordy

New Member
Jan 27, 2017
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Jul 14, 2017
#1
  • Jul 14, 2017
  • #1
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
-----------
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
-------------

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

SendMeUrDataLog
10 Year Member
Apr 6, 2011
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Hillsborough county
Jul 14, 2017
#2
  • Jul 14, 2017
  • #2
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.
 
Reactions: Davedacarpainter
T

Too Fordy

New Member
Jan 27, 2017
9
0
1
Jul 14, 2017
#3
  • Jul 14, 2017
  • #3
a91what said:
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.
Click to expand...

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

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
6,721
214
Hillsborough county
Jul 14, 2017
#4
  • Jul 14, 2017
  • #4
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

I’m not much help unless you’re looking for ****!
Founding Member
Nov 29, 1999
5,896
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129
Morgantown, WV...where couches meet their doom
Jul 17, 2017
#5
  • Jul 17, 2017
  • #5
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.
 
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