1986 Ford F150 Starting

1986 FORD F-150
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86FORDF150
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Engine Mechanical problem
1986 Ford F150 V8 Two Wheel Drive Automatic

My truck is a 5.8 2bbl carb truck. I just installed a new ignition lock cylinder. Even before with the old one if I had the keys out of the truck and I hook up the negative terminal it wants to start even with no keys in the truck. The engine turns over and cranks. What is the cause of that and how can I stop it.
Oct 11, 2008 at 6:54 AM
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BLACKOP555
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negative terminal from what to what.

other then that does it run just fine?
Oct 11, 2008 at 8:31 AM
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86FORDF150
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The negative terminal on the battery. If you hook up the black wire to the negative terminal on the battery with the positive hooked up already the truck wants to start cranking with out any keys in the ignition.
Oct 11, 2008 at 2:16 PM
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BLACKOP555
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so basically the second the battery is hooked up normally the starter engages.

disconnect the S wire off of the starter relay, it just pops on and off.

then hook up battery same thing?

does it stop the cranking untill S wire is put back on?
Oct 12, 2008 at 1:26 AM
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86FORDF150
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yes my truck does still try to crank and start with the s wire off still.
Oct 12, 2008 at 5:11 AM
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BLACKOP555
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sounds to me like the ignition coil may be fused together with itself causing the starter relay to just bypass the switch and just crank.

when using a new relay, make sure batteyr is fully charged when starting each time or youll ruin the new relay.
Oct 12, 2008 at 10:38 AM
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86FORDF150
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on my truck what should I do and how can I fix this problem?
Oct 12, 2008 at 1:35 PM
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BLACKOP555
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i would replace the starter relay as its staying on with the s wire removed, which is the signal that comes from the ignition switch and neutral safety switches..

its the thing that the s wire hooks too and the battery cable goes from to the starter.
Oct 13, 2008 at 11:05 AM
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86FORDF150
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So your saying to replace the starter selinoid relay. The one on the inside fender? Or which one and where is it located?.
Oct 13, 2008 at 11:16 AM
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BLACKOP555
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yes the one on the inner fender. is that the relay you pulled the S wire off of?
Oct 13, 2008 at 2:08 PM
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