Engine starts then stalls, code P1300

Original #1 circuit coil got hot and burned up, changed out the #1 igniter coil to a new one. As soon as ignition switch was turned on, that one burned up as well.
What might be burning up the coil? Only getting the P1300 code.

 

You check the plug as well?

Some other threads I did not read through them all.

 

Thanks for the links, I've thru it all.

 

Did it burn up as soon as the key was on, or did you try and crank it over?

When's the last time the ignition cables have been replaced?

Plugs replaced?

 

I cranked it over, then it would start and run for a few seconds, then die.
After that, I had to leave the key in the "on" postion in order for the coder to connect with the ecu and
read the codes. I know on much older motors, if you leave the key in the "on" postion and not start/run for an extended time
it will burn the coil up. I thought with the advent of electronic ignition, that was no longer an issue and have not had it happen before
when trouble shooting while using a diagnostic tool.
This runner has over 240,000 miles and I doubt the plug wires have ever been changed. Plugs were changed a year ago. I'm not sure I understand how a bad plug or plug wire would cause the coil to burn up.

 

Spark Plug wires with high resistance will burn up coils. You need to change them all...like 50k miles ago.

 

https://isavetractors.com/blog/do-you-keep-burning-out-ignition-coils-here-is-why/

 

Remember, this is a very quick cooking (in seconds) of the coil. A week or faulty wire could cause an issue over time
but I just don't see it happening that quick.
I took a look at the wires, they are not stock, so have been changed at some point. I checked the bad coil to spark plug lead and
it ohms at 5.75 (using 20K on the meter) which should be very good.
Spark plug checked out at 5.17, in the middle of the specs.

 

Only other thing I can think of is the ICM. (Ignition Control Module)

https://www.yourmechanic.com/questi...ion-coil-same-spot-not-spark-plug-by-wesley-g

I would check the coil packs, wires, plugs and ICM and see what has been replaced at some point. Look for a cheap ICM (installed by Prev Owner). Maybe get a picture that this is the recurrence of an old problem.

With such a quick burn out...you would think there is a short somewhere...but there is only so many parts to this system.

 

I have ordered plug wires, new spark plugs and new coil. Also picking up a good used ICM.
While taking the coil back out, we noticed a very small spot, could barely see, on one of the two wires
that are part of the connector into the coil. I could not see clear sign of burn thru, but am suspecting at this point
that it was grounding the circuit. When the coil comes in, I will install a new connector end and try to start up before
changing anything else. Will take extra precaution not to burn out the coil.

 

I would bet that's it. Cheap wires are never to be trusted. My opinion is to only replace ignition components with TOYOTA brand stuff that runs for 250k miles. For the ICM, a good used one is the best bet as they are really pricey from the dealer.

 

the plug wires seem fine and ohm out in spec. The wire with the issue is part of the original harness wire that runs to the connector that snaps into the coil. I will check it out when the other coil comes in and take a picture to post. Hope that is it!

 

update-
It was an issue that I described with one of the wires running out of the harness then into the coil. There are two sizes of wire
that run to the coil connector and the one at issue was the smaller size wire.
Back toward the head, a very small break or rub thru hole, barely visible was located and a shrink wrap
piece applied over it. Installed new wire clip and a very cheap new coil back in for testing and it fired right up and stayed running.
Never changed spark plug wires or plugs as they looked and ohmed out in spec. Have a used igniter coming and will keep it for a spare.
I hope this helps others to not run down the rabbit hole!!
Thanks for all the help, it is good to talk with others that know these vehicles.

 

That's a hell of a find! Nice work.

 

That's about the only thing I knock the 4Runner for...the engine harness...or more specifically the shitty plastic "loom" they used just disintegrates and you can't buy a replacement.

When I did my valve covers, I used a roll of electrical tape to completely wrap what was left of that plastic loom. If ever the intake comes off the car again, I have corrugated looms and fasteners that I will use to bolt the harness back in better than Toyota did it.

If I were you, I would look at doing similar. If you have 1 worn wire (and from the pic, looks you had others), you're gonna have more of the same issue, especially if they just lay on the engine and the heat gets to them.

 

I forgot to mention that I put the scan guage back on, cleared the codes and then ran a code check.
No codes came up, 4runner seems fine now.

 

Mines doing the exact same thing and I’ve been stumped... I’m literally about to walk out here now and see if this does the trick!

 

A quick note, if I may. When you put heat shrink on a wire, most especially in the engine compartment, us the melt-wall shrink. Also known as FIT-300. It has a lining on the inside that melts and flows when you heat it up to shrink it. It fills in any air spaces, and serves perfectly to keep the gunk, that can damage insulation, or get down into the wire inside the insulation and corrode it, that runs around engine compartments, out. Fuel fumes, battery acid mist, exhaust, you name it.
Melt-wall is the way to go for heat shrink in the engine compartment, or really, anywhere. You never know what could sneak in. It's a little more expensive, but WELL worth the money.
McMaster-Carr carries it in all sorts of sizes and colors. Really good source. I could post a link, or just google McMaster-Carr. You'll find it. They're also an awesome source for hardware, tools... you name it, they got it.

Have fun all!
Pat☺

 

Is that like the "Marine" shrink wrap you can get at harbor freight? I got some of that a while back. It's supposed to seal the connection like you describe. Probably not as good as FIT-300.

 

Similar, yeah, but better. The quality shrink is FIT-200. The highest quality melt-wall is the FIT-300. Those are actually the Mil-Spec part numbers. What the military uses.

We used the FIT-300 on the F-4 Phantom radar systems I worked on, and if it can stand up to what a modern, relatively, jet can put it through, it can stand up to ANYthing a vehicle can throw at it!

McMaster-Carr is definitely the way to go. That's where we got it from. That was 40 some-odd years ago, and they're still around. They've got the good stuff

Pat☺