Hi everyone. I have a 01 f150 with 5 4
I'm currently suffering with the dreaded misfire warlord.
After scanning and getting misfire on cylinder # whatever, I went to replace said coil pack.
as I was mid way thru, I noticed a single wire coming off cylinder #1 coilpack, that runs alone around the back of the throttle body, and ends up around cylinder 5&6 and is not connected to anything

Anyone have any ideas?
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Someone probably installed aftermarket tach at some point would be my guess. Does your tach work?

 

Ya my tach works great. All stock gauges.

The wire is in black corrugated wire sheathing like car stereo shops use. I'd at 18-22 awg. Is not long enough to reach drivers side dinner fender or even brake master. Its length gets it just clearing the drivers side valve cover by a few inches

 

Other probability is for a remote start that required a tach input.

It's not "factory".

 

Thanks that maybe a possiblity as it has aftermarket alarm.

So this wire being there won't be causing my misfire?

 

Yes, it should cause a misfire... How could it cause a misfire? A bad connection at where they've tapped in to it. You really need to inspect that wire and see.

 

Assuming it is for the auto start, where would that typically lead to? Alarm head unit or do they go to a relay or something like that?


Really appreciate this.

 

If it is for tach signal, my guess is that it would most likely go directly to the alarm. I don't see any reason for a relay there.