Hi everyone, I am new to this forum (and forums in general).
I have a 4.2L 97 F150 with 170000 miles (manual trans if it matters).
The truck started giving horrible MPG and seemed to require alot of throttle to take off. Also, once I shifted to second gear and pressed the throttle, the engine seemed to give out or miss. I did an OBDII scan and saw that cylinder 3 had thousands of misfires and the number of misfires went up as I drove.
What should I do?

I am somewhat mechanically inclined and an avid DIYer so I am hoping this is something I can fix myself. Any help will be appreciated, thanks.

 

first of all welcome

and it could be a bad spark plug or a bad c.o.p. (coil pack)

the first thing i would do is replace the spark plug in that cylinder, if that does not work then its probably your c.o.p.

 

Thanks for the welcome and the reply spencer =)

I replaced the plugs around 2000 miles ago so I assume it wont be them (right?). Is there a good way to test the coil pack? Any chance its bad wires?

 

here's a link on how to test a coil pack

https://www.f150forum.com/f6/how-test-coil-pack-17249/


and its probably not your spark plugs, there good for like 100k miles.

and i would check the wires that lead to the cop, and also the connector may be lose for some reason, and check if the coil pack is all the way down and connected to the spark plug.

also have you washed your engine or has it been soaked with water, because that can kill c.o.p.'s ive learned that from experience

 

I am going to try to test the c.o.p and I will check all wiring/ and plugs to ensure proper fitting.

I bought the truck used so I dont know for sure if the engine has been washed or not. Now I know not too though, thanks for the tip!

The help is greatly appreciated