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Spark in one cylinder

  • Thread starter Thread starter fordkid
  • Start date Start date Dec 1, 2009
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BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
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18
108
Chicagoland
Dec 7, 2009
#21
  • Dec 7, 2009
  • #21
Thread merged with previous thread on this subject.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Dec 7, 2009
#22
  • Dec 7, 2009
  • #22
fordkid said:
allright, a little update and a few more questions.

first off for anyone new to my problem I am working on a 66 mustang with a 5.0 motor and T5 from an 86 5.0 mustang, I am keeping the Fuel Injection and I have transfered all three main wireharnesses over to the 66, the Main ECU harness, the Front light Harness whitch also has the hook up for the COIL, and the rear light harness whitch also has the wireing for the fuel pump. I am using an aftermarket elecric fuel pump mounted outside the tank.

I am only getting spark in ONE cylinder, I have fixed the fuel pump porblem it comes on and shuts off just like it is supposed to do. I turn the key on and it comes on for a few seconds and then it goes off. Was very glad to get that part of my problem fixed, a Big thanks to everyone who helped me with that. I am also using the Coil and the Ignition relay from the 86, basicly bypassing the whole electrical system on the 66.

question on the one spark issue. I have 12 volts to both sides of the COIL, is that right. I was thinking one side should be hot and the other should be ground. but both have 12 volts with the key in the ON position.

also I am thinking my clutch saftey switch isn't working proprly, since it's not hooked up to the pedal since the pedal is the 66 pedal and not the 86 pedal. so to try and start the car I have just been jumping the Ignition relay with a screw driver from the Hot terminal to the small screw terminal. could that be my problem with only getting spark to one cylinder. I doubt it but figured I would ask.

I know I know, the harness kit would be easier but I am not willing to pay 600 bucks just for a wire kit. the head aches are FREE,

Thanks
Ford Kid
Click to expand...

It normal to have 12v on both sides of the coil with just the key on. Power travels through the coil windings. The TFI just momentarily grounds the coil for it to pulse and throw a spark. So dont ground it straight to the body.

Just use a blade fuse in the black connector for the clutch switch. That should allow power to reach the starter relay when the key is turned to crank mode.
 
F

fordkid

New Member
May 28, 2007
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Dec 8, 2009
#23
  • Dec 8, 2009
  • #23
good to hear, now I can move on to something else. I found this vacum device with some wires going to it. I belive the wires go to the fuel injector harness. and the other end of the vacum hose goes to the upper intake manifold underneath on the drivers side. I can't seem to figure out where to hook it up at. for the life of me I don't remember unpluging the device when I took the engine out of the 86. check out the pics.

I also thought I would include a pic of the speed density device(can't think of the proper name) and it's vacum line just to see if anyone can see something wrong with it.
 

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HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Dec 8, 2009
#24
  • Dec 8, 2009
  • #24
I can't get the pics large enough to see (without graining them out). You probably are looking at something for the A.I.R., EGR or EVAP system though.
 

hotrodredneck

New Member
Jul 28, 2004
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Newport News Va
Dec 8, 2009
#25
  • Dec 8, 2009
  • #25
also, if you are running a normal distributer, and are getting spark to one cyl only, then somthing is wrong with your distributer, or cap and rotor. Tak your distributer cap off and make sure the rotor is in the right spot, not just jammed in there so it doesnt rotate.
 

BlackGT89

Member
Dec 16, 2002
774
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Huntsville, AL
Dec 8, 2009
#26
  • Dec 8, 2009
  • #26
hotrodredneck said:
also, if you are running a normal distributer, and are getting spark to one cyl only, then somthing is wrong with your distributer, or cap and rotor. Tak your distributer cap off and make sure the rotor is in the right spot, not just jammed in there so it doesnt rotate.
Click to expand...

I suggested that too and Ford Kid said the rotor did turn back in post #7. Spark in one cylinder is one for the books !

I hate to say throw some new parts at it but maybe a new (or borrowed) cap and rotor (or complete distributor) are in order ? And maybe ohm out your plug wires or do some substitution and see if that changes anything.
 

hotrodredneck

New Member
Jul 28, 2004
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Newport News Va
Dec 8, 2009
#27
  • Dec 8, 2009
  • #27
it could also be the ignition module on the distributor. It's the little silver rectangular thing on the front of the distributor
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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Dec 8, 2009
#28
  • Dec 8, 2009
  • #28
Have you checked for injector pulsing yet (it might have been lost in one of these long posts)?

If you turn the key on and turn the motor over by hand, you should hear the FP re-prime and the injectors click. If not, look for carnage around the PIP (like a reluctor wheel that's about to fall off or mangled, a PIP that looks nasty, or metal around the bowl of the dizzy).
 
F

fordkid

New Member
May 28, 2007
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Dec 20, 2009
#29
  • Dec 20, 2009
  • #29
ok so here goes, not sure why this happend, but I was doing some substitution with the wires, first taking the one that I was getting spark out of and switching it with the one right in front of it at the plugs, leaving the distributor end of the plugs the same, sure enough the spark stayed in that wire witch was now hooked up to a different cylinder. so I switched it at the distributor end and the sparked changed wires. now still comming out of the plug on the distributor as before but with a different spark plug wire hooked up to it. then I switched that plug with a plug on the different side of the engine. the spark followed that wire. so now I was still getting spark to that one wire but now it was routed to the other side. I switched the wire back to the original cylinder it was hooked up to before and all of a sudden I have spark in every wire and the motor starts up and sounds great. so I figure since the problem was never found I am going to assume it is in the distributor cap and somehow it fixed it self as I was moving the wires around. so I will replace the cap and rotor and run the car, I am sure the problem will come back when I least expect it. just glad the motor is running, now a few more things needed like clutch cable and and throttle cable and I am on the road.

Thanks guys, your help was much appreciated.

Ford Kid
 
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