CEL P0351 Ignition Coil "A" Primary Control Circuit/Open

[gramicci101]

I second the better airflow suggestion. I'm about to move to a very hot climate and am starting to look at vented hoods or opening up the fender trim to vent heat.

Also, some sort of heat sink between the coil and the header. Preferably with air moving over it. Or just a heat shield between them.

[ATL BRZ]

Originally Posted by gramicci101

I second the better airflow suggestion. I'm about to move to a very hot climate and am starting to look at vented hoods or opening up the fender trim to vent heat.

Also, some sort of heat sink between the coil and the header. Preferably with air moving over it. Or just a heat shield between them.

Good suggestions. I think the cheapest and easiest way would be to start with a metal heat shield for the coils that extends over the header and op to block heat from getting near the passengers side coils.

This would be a great opportunity for a parts manufacturer for this platform to step in and fab up a solution for testing and a possible new product release. Everyone that tracks their 86 could potentially benefit from something like this if it makes the coils last longer, which it very well should.

@Wonderbar , @GrimmSpeed , @Touge Factory , @CounterSpace Garage , @PERRIN

[gramicci101]

Originally Posted by ATL BRZ

Good suggestions. I think the cheapest and easiest way would be to start with a metal heat shield for the coils that extends over the header and op to block heat from getting near the passengers side coils.

A heat shield would definitely be the quickest and easiest. Especially if you coated the hot side with that gold foil I've seen people use around the forum.

One potential problem is that while the various manufacturers' headers tend to follow the same general path, I can see there being enough variation that a one-size-fits-all solution may not be practical. Especially between EL and UEL headers.

My other problem is that that just reflects the heat, which still has to go somewhere or something else will cook. I'd prefer to dissipate the heat if possible.

When I get to vegas I am definitely going to drop in a koyo radiator, forester oil cooler, and open up the fender trim to vent heat. These cars run hot enough as it is.

Edit: info on the oil cooler: clicky
I spoke with CARNZ about the possibility of using the coolant lines from the throttle body instead of running coolant from the block, especially since I was going to disconnect those anyways, as you did here; this was his response.

Originally Posted by CARNZ

I don't see why you couldn't do it that way. It shouldn't hurt anything, i would route the hose that comes off the heater pipe on the back of the engine to the smaller side of the oil cooler(side that faces the drivers side). Then route the other throttle body coolant hose to the inlet of the oil cooler(passenger side port)

[ATL BRZ]

Originally Posted by gramicci101

A heat shield would definitely be the quickest and easiest. Especially if you coated the hot side with that gold foil I've seen people use around the forum.

One potential problem is that while the various manufacturers' headers tend to follow the same general path, I can see there being enough variation that a one-size-fits-all solution may not be practical. Especially between EL and UEL headers.

My other problem is that that just reflects the heat, which still has to go somewhere or something else will cook. I'd prefer to dissipate the heat if possible.

I was thinking about a smaller bolt-on shield that doesnt focus too much on covering the exhaust below, but more directly covering up the coils and reflecting the heat that rises up off the exhaust away from them, but not trapping it.

Brace yourselves: shitty mspaint inbound



or



Something like the above. Could have a hole drilled where the coil bolts in so you install the shield with the same bolts.

[gramicci101]

I hadn't looked at it like that. I'd leave the top open so any heat could escape. Is there a way to get airflow in there?

I edited my previous post to include info about the forester oil cooler, as well.

[ATL BRZ]

Originally Posted by gramicci101

Is there a way to get airflow in there?

Sure, there's a way, I'm running ducting to my brakes right past that area, but I need all that air for my rotors...

[gramicci101]

Originally Posted by normancw

The driver APR side duct would just cool the windshield washer tank!

Guys, this is a critical problem that I don't think has been addressed. We can't let the windshield washer tank overheat.

Seriously though, you could run cool air over the coils on both sides. I can't see how that would be a bad thing.

[gramicci101]

How does APR recommend running the driver's side duct? Through the same place the tf duct goes?

[ATL BRZ]

New revised part # OEM coil arrived.

I thought about getting some gold heat tape and putting some on the top part of the coil that is exposed but I don't have any and it would take a few days to order and ship, and I wanted to fix the P0351 as soon as possible.



Only one 10mm bolt holding it in. I just replaced it myself rather easily in about 20 minutes. Removed the three 10mm bolts holding in the ECU on the black fuel rail cover carefully after stuffing some shop towels below to catch any dropped bolts. Zip tied the box out of the way on the strut brace so it doesn't slide into anything. Then I grabbed the coil and pulled it straight out and then up to get the whole thing out. Pressed the connector down and pulled it off and the new one went back in just as easily. Just need patience and dexterity and it's pretty painless. The drivers side coils wouldn't be as easy, though, since there's more stuff in the way.

I put everything back the way it was and secured all the bolts before starting it again. Then I went for a drive and got everything nice and hot before doing a couple WOT pulls to redline and all is well. No more CEL.

[gramicci101]

Here's a quick sketchup of a simple heat shield. The bolts holding the coils in are sunk into the engine, so I used the bolt just forward and below the front coil and two of the bolts above the coils. I couldn't see the back or bottom edges to locate mounting points, but the heat shield should attach there as well to prevent rattling. I don't have the capabilities right now to make this, but I'm sure someone like @Wonderbar or @GrimmSpeed could whip this up pretty quickly. The top and back are open to allow heat to escape. Gold foil on the outer surface to reflect heat away from the coils.







First Edit And you actually don't need the holes through the shield for the coil mounting bolts. I put those in when I was still considering that option for mounting the shield.

Second Edit Here's an additional tweak. I flared out the front edge to draw air from the engine bay over the coils, rather than have them sit with no air flow. This way, if the heat from the exhaust soaks through the heat shield during hard use, it can be flushed out with (hopefully) cooler air from the engine bay.





Third Edit If you wanted to get really frisky with it, you could rivet a heat sink to the inner surface. Using the airflow from the flared section on the leading edge, this would help to dissipate any heat that soaked through the reflective outer surface before it reached the coil.

I think that's about it from me for the moment. I always get caught up in incremental changes and improvements when I use sketchup.

[ATL BRZ]

Originally Posted by gramicci101

Here's a quick sketchup of a simple heat shield. The bolts holding the coils in are sunk into the engine, so I used the bolt just forward and below the front coil and two of the bolts above the coils. I couldn't see the back or bottom edges to locate mounting points, but the heat shield should attach there as well to prevent rattling. I don't have the capabilities right now to make this, but I'm sure someone like @Wonderbar or @GrimmSpeed could whip this up pretty quickly. The top and back are open to allow heat to escape. Gold foil on the outer surface to reflect heat away from the coils.

DUDE! AWESOME WORK!

[gramicci101]

I love sketchup. I use it mostly from home audio, but it's a great and fun tool. All my stuff, including audio, can be found at http://rsvr79.imgur.com/.

I PM'd GrimmSpeed to see if they'd be interested. I know they have a lot on their plate right now though.

[ATL BRZ]

We should keep bugging @Wonderbar , this is right up his alley

[Wonderbar]

I might could punch it out. Let me look into it.