CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

4 Coil Packs in 4 weeks ? 2007 Ford Ranger

Posting this for a friend who has a 2007 Ford Ranger 3.0 V6 and auto 53k miles. Truck ran fine until one morning when he started it up and was missing like crazy with check engine light flashing … Could not get vehicle to go over 30 MPH so had it towed to a mechanic. He said it sounded like it was running on 3 or 4 cylinders with raw gas smell out of exhaust.

Mechanic said coil pack bad and replaced. 3 days later same symptom, mechanic replaced coil pack again.
Same thing again 2 weeks later. Making a long story short replaced with coil pack number 4. Mechanic stated he found a bad plug wire and replaced,

He never inspected the spark plugs.
Got truck back tonight and running fine "for now ". I am an older fellow who has older cars with carbs, points etc
so not too up to date with newer models.

What would cause 4 coil packs to go bad in a month ? I am saying “maybe” bad spark plugs.

Maybe you guys can give me some info on what would cause this issue as I told him he should dump
this mechanic and find someone else. I feel like going over to his home and pull the plugs to check them
or just replace out of my own pocket making sure gap is set correctly etc, as he can’t afford much more
of this right now.

First time he was charged 150.00 to replace the coil pack, 2nd and 3rd under warranty, now he socked
him another 160.00 for the fourth one and a new plug wire.

Also my friend advised that he can hear the coil pack "clicking " I thought maybe an over voltage problem with alternator but says he has a steady 13.9v through different RPM ranges so ok there.

I can’t advise on the cause, but I’m with you he needs to find another mechanic. You don’t go though 4 coils in a month unless there’s an underlying problem and the mechanic should have known this and checked things out more closely.

Your friend does not have a truck problem; he has a wild guessing mechanic problem, and apparently a bad guesser at that.

There’s not enough info known to know what’s going on with this truck but if for the sake of discussion one assumed that the original coil pack actually failed and all of the following coils actually failed also this would mean the coils are being killed by something else.

Bad spark plugs, something causing major misfires (fuel pressure regulator, crank sensor, etc, etc), bad plug wires, and so on could cause this kind of problem.

The plugs should always be looked at as plugs can kill everything clean back through the secondary ignition system and I think you’re on the right track by considering plugs and even wires.
The “clicking” sound could very well be the sound of a spark jumping to ground on the cylinder head and if so this is going to kill the wire and coil soon.
With the engine running at night and shielded from any light take a look around and see if you can spot something popping around in there.