WD 40

I had a slew of misfires on cylinders 4, 6, 7, and 8 about 2 months ago. I changed out plugs and wires, and the issue went away. A month ago I had similar issues and changed out the passenger side coil pack, again, problems went away. Last week I was driving up a mountain road for work and I had no torque, or power and barely made it to the job site. After working I called my boss and told him I was taking it to a shop. $399 and 5 hours later, I have new plugs and cylinder 4 had what looked to be coolant above the plug. They wanted to change an O2 sensor but the shop was closing and the guy said to bring it back. Searching online leads me to think the head gasket could be bad or possibly a crack in the head. Today going up the same mountain, it threw codes for cylinders 5, 7, and 8. Should I take this back to the same place or to someone that specializes in engines? I live in Chattanooga, TN, and don't know what to do next. The truck has 190,000 miles on it and is in excellent shape. I don't see spending $10,000 plus on something newer if I can spend $3k-4k and keep this one running. It has been my daily driver since 2004, and I don't really need all the bells and whistles on something newer with higher insurance premiums. I don't finance vehicles, just pay cash for them.

10thGenFnatic

I also live in chattanooga tenessee, and i know that there is only a few shops around here that deal with engines, i repair most of my stuff myself, but there are a few decent mechanics around here

fordguy2100

What brand of cops and spark plugs were used?
Might want to try a compression test and see where your numbers are at. That will help lead the diagnosis in the right direction

Jbrew

Agree w/FG2100. Without the details, it's difficult to say. The vehicle doesn't have COP's.

WD 40

Motorcraft plugs and ignition coils from O'rileys. I have no idea how to do a compression test. I'm an IT guy turned trim carpenter/handyman for the time being. Any walkthrough/tool I can buy to test that myself? Tired of feeling scammed...

Jbrew

Make sure you don't have Autolite plugs in that 98. They lasted all of 40 miles in my old 98 before two of them turned colors and stopped firing. I didn't think I was going to make it back to the house either lol.

fordguy2100

Didn't watch the video, but this guy normally goes over steps in a very simple manner

Jbrew

Check compression.