1996 7.4 mpi efi still no spark
#1
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im still working on the problem redid all the grounds replaced the moduel, coil , i started once and ran about 2 mins and quit and wont start now as usual , i have 11 volts to the coil and when cranking it goes to 9 volts is that enought to make it start any jhelp appericated thanks again james
#2
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im still working on the problem redid all the grounds replaced the moduel, coil , i started once and ran about 2 mins and quit and wont start now as usual , i have 11 volts to the coil and when cranking it goes to 9 volts is that enought to make it start any jhelp appericated thanks again james
You have that white big fuse on the starter motor? sometimes there is a bad connection inside, try hooking all positives directly without the fuse and try again. Why you replaced the module & coil?
#5
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9 v will not do it..
your starter could be getting ready to fail pulling to many amps drawing the volthage down. If I remember right you must have close to 12 v for the ECU..
You could wire 12 v direct from another source to your ECU and then start your motor. If it starts,, thats your problem.
On some hot rods I had with MSD ign box's, they had to have a certain voltage or they would not fire (period)
your starter could be getting ready to fail pulling to many amps drawing the volthage down. If I remember right you must have close to 12 v for the ECU..
You could wire 12 v direct from another source to your ECU and then start your motor. If it starts,, thats your problem.
On some hot rods I had with MSD ign box's, they had to have a certain voltage or they would not fire (period)
#7
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Joined: Apr 2009
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9 v will not do it..
your starter could be getting ready to fail pulling to many amps drawing the volthage down. If I remember right you must have close to 12 v for the ECU..
You could wire 12 v direct from another source to your ECU and then start your motor. If it starts,, thats your problem.
On some hot rods I had with MSD ign box's, they had to have a certain voltage or they would not fire (period)
your starter could be getting ready to fail pulling to many amps drawing the volthage down. If I remember right you must have close to 12 v for the ECU..
You could wire 12 v direct from another source to your ECU and then start your motor. If it starts,, thats your problem.
On some hot rods I had with MSD ign box's, they had to have a certain voltage or they would not fire (period)
#8
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Joined: Jan 2004
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From: Tennessee
The purple wire in the 10 pin harness may have some corrosion on it, not allowing full voltage. Power to turn on the ecm and the ignition comes from the key switch. As mentioned, try tapping into the purple wire with 12 volts and see if it cranks. If it does, pull apart the 10 pin plug and clean it.
Eddie
Eddie
Last edited by Young Performance; 10-13-2012 at 12:49 PM.
#10
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From: Tampa Bay Area Florida/ North Miami Florida
If you have one dead battery and one half good one and put the switch to both, the bad battery will be draining the good one especially during cranking. Pull the bad battery and just work with the one good one to start with.
Chris
Chris



