Truck Mechanic Question

[McPatrickClan]

I am nearly 100% sure that one of the coil packs in my 2000 Ford F-150 needs to be replaced. I would rather not pay to replace all eight of them. Does anyone know specifically, without a Check Engine Light being on, how I can tell which cylinder is misfiring and which coil pack needs to be replaced?

Thank you!

[Slick8]

I've had two coil packs go out on my 01. You'll know you have a problem, missing, backfire, sputtering and no power. Both times the check engine light came on.

I simply disconnected the leads from each coil pack and tested it with an Ohm meeter. Both were completely open, but if you had one with a drastically different resistance that would be you problem coil as well. Per Ford you should also change that spark plug.

I would only replace it with a Ford coil pack ($55 about four years ago) but bought one from AZ at half the price to keep in the truck for an emergency.

Good luck.

[McPatrickClan]

Why only a Ford coil pack instead of Auto Zone, MSD, something like that?

[Traildust]

Check these guys out for your parts

TascaParts.com ......they are a LM-Ford- Mazda parts house

[cjkozik]

the wifes expedition had the same problem.. bad coil and no check engine light on... I took it took my buddy at ford and he put his computer on it and the #6 cylinder had a misfire, but before i took it to him i had unplugged each coil while the engine was running one at a time and when you unplug a good coil the engine will run rougher and when you unplug the bad coil your not gonna be able to tell that you unplugged anything.. i had it narrowed down to the #6 cylinder and he just confirmed with the computer.

[Goldeneagle]

Just for grins you might want to try replacing the rubber boot on the coil pack when you figure out which one it is. The rubber deteriorates and starts firing out the side. A plug boot kit costs about $6. I replaced several coil packs before I figured this out.

[Capuchin Monkey]

i bought a AZ coil pack for $43.00 and it works.

[McPatrickClan]

I just wish I knew how to diagnose which one it is....

[Goldeneagle]

I just wish I knew how to diagnose which one it is....

Start the truck. Be real carefull and pull the connector off the coil packs one at a time. They won't bite ya like regular plug wires do. If the motor changes RPM or starts running rougher it's NOT that cylinder. When you find one that does NOT make a change in the way the motor runs, you found your bad one. When you pull it check the condition of the boot. They get old and cracked and will the spark will go through the sides instead of to the plug. A $6 fix at O'Reilly's.

[PSD Ryan]

If you dont wanna do all that start pulling spark plugs. The jet black soaking wet one is probably your bad cylinder.

[Goldeneagle]

If you dont wanna do all that start pulling spark plugs. The jet black soaking wet one is probably your bad cylinder.

On another thead, I think he said he is getting codes showing running lean. I don't think he will have one soaking wet if the computer has leaned out the fuel.

[PSD Ryan]

If it's a coil pack it will be. I had the same problem on my chevy. It said running lean, but it was spitting gasoline out the tailpipe.

[Goldeneagle]

These things will drive a man crazy. I was getting lean codes and the plugs looked fine. Found out it was sparking through the boot and the plug was still firing. Just not enough to run properly. Did you know it will throw a code if your dip stick tube is not inserted all the way into the engine block? Took me a looooong time to find that one.

[McPatrickClan]

I think I'm just going to bite the bullet and save up to replace all the coil packs. They need it in a year or so anyway.