Burnt out ignition coils

Just thinking the same thing. The engine compartment is not a sealed environment. It's designed to withstand a certain amount of moisture

 

Ever seen three on one side all go at once like this on a relatively new vehicle?

 

Nope

Its fishy but the codes following the coils is the correct to troubleshoot it.

As long as they're not fudging codes

 

Suspicious. Oh well. Work is done and money is spent I assume.

I’m a cynical bastard.

 

I do recall one case of injector failing, kept blowing the INJ fuse on a 3rd gen...
Took a LOOONG time to diagnose
https://www.tacomaworld.com/threads/10a-inj-fuse.687333/

 

Welcome, and sorry to hear about your troubles.

The dealer's excuse for the coil failure sounds so lame to me, that it leads me to believe they caused the issue and didn't want to absorb the labor time it took to correct it.

That said, I wouldn’t worry as these coils as they are pretty reliable. I know because I have put 425+k miles, on 24 coils combined (four vehicles) with these coils and not a one has ever failed.

This includes high water, very high water on at least two, and at least one that was over the top due on spark plugs change and still no sign of failure.
Not even a hiccup, zero, nada.

 

OP........FWIW. Busting through snow drifts can pack snow into the engine compartment. Snow could easily migrate to the top of the engine.

Once upon about lifetime or 2 ago, when I was a young ID10T. I was driving a small hatchback. Driving home from work during a blizzard, busting multiple drifts, then hitting a drift that wasn't deep but about 2 car lengths wide......I made it through. Less than a mile later the car suddenly died. I opened the hood to only see the air cleaner surrounded by snow. Fortunately, a passing motorist gave me a lift home. Dad and I towed the snow packed car home. It was a serious thaw and clean up, plus repair of several electric components.

Suggest to avoid "drift busting". It can put pounds of snow in the engine bay.

 

I've seen many coils from Toyotas over the years, and even good coils can show slight water intrusion.

If an entire bank is misfiring we've seen injectors cause this on the 3.5 tacomas.


Make sure to hold onto it incase the issues return.

 

I don't have a 3rd gen so I can't go look but isn't that the bank that's under the intake manifold and kind of hard to get to? Maybe they just sold three coils as a set because they didn't want to have to take the intake back off again in the future

On my 4.0 liter there is a bank that's under the intake manifold but you can still get the coils out easily, not sure it's the 3.5 is more covered up

 

It's very similar, there's a little bit of noise reduction material but they are nearly the same to replace. A touch harder on the 3.5.

 

This makes more sense to me. If they replaced the pump and some debris made it to the injectors...

 

Correct me if I'm wrong but isnt that series of codes (p0351/2/3 etc) an "ignition event" fault?

The codes followed to the other bank


Maybe he parked under some power lines

 

Curious how long it took to diag. If it was an hour long diag, I'd say chances are they never swapped coils. Half a day? Maybe true. Me personally, I'd be asking how the techs went about changing coils, and inspecting associated bolts that pertain to coil removal.

 

Hey Tacoma World members, sorry to cut in on the tread.
I have a 2018 Toyota Tacoma 2GR-FKS of a mates.
I work for a Toyota Dealership in Canada here and been a mechanic for 17 years now.
I read through this thread because I have a similar story. Although it’s not the coil packs?
I’ve spent a few hours diagnosing the truck in my mates garage in sub zero temperatures.
He claimed he didn’t plug the block heater in one morning and started the truck. Then it started running rough and Engine light came ON.
Using a generic scan tool he pulled dtc’s P0351 for Ignition Coil ‘A’ Primary/Secondary Circuit. P0353 Ignition Coil ‘C’ Primary/Secondary Circuit and P0355 Ignition Coil ‘E’ Primary/Secondary Circuit.
Did the switch coils with number #4 (being easiest access) cylinder to #5 and cleared codes. Only for the same codes to return.
Pulled a spark plug out of #5 cylinder and it was wet from gas no moisture in the tube. I got a wiring diagram from work and traced wire IGF1 back to ECM but has continuity....
I’m shit out of luck.
It’s -25°C out. I thought it would be condensation/ moisture too.

 

With those primary circuit codes, if it isn't a bad coil the pcm is suspect. The drivers that ground each coil can fail

Sounds like you've checked the harness.

If you have access to a scope you can watch the pattern of the pcm (hopefully) turning the primary side of the coil on and off

 

@Dm93

 

What did ya use to check continuity? Need a load that's similar to the current of the real load. Sorry if I'm speaking on something you already know.

Also, grounds are good too? Anytime multiple things fail on a single circuit, my gut goes to grounds. But I am by no means any expert at all

 

Did you check power and ground at the coils that are not working?
A scope would be needed to check the control and feedback signals but it shouldn't be too hard to narrow down if you had one.

 

Hey Dm93 and Skydvrr, I checked a few earths with the points on my wiring diagram. Couldn’t find terminal EE which is on the Toyota wiring for the coils.
I basically checked what was linked between 1, 3 and 5 and the white wire IGF1 from coil #5 to the ECM and got continuity with my multimeter.
Just it’s usually just the coil packs that burn out and switching them over to the other side usually verifies that. Not the case here. I was going to look at the Inj fuse 10amp but didn’t think it was necessary as you would think the truck wouldn’t start if that was blown.