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

[Wonderbar]

I don't imagine heat sinks not attached to the coils would do anything, since they are designed to pull heat away from what they are attached to. Aluminum with heat shielding probably is the easiest route.

[ATL BRZ]

Originally Posted by Wonderbar

I don't imagine heat sinks not attached to the coils would do anything, since they are designed to pull heat away from what they are attached to. Aluminum with heat shielding probably is the easiest route.

Keep us updated, please. I'd really like to see this come to fruition. Everyone can benefit from this since both stock and modded/tracked cars have experienced premature coil failures with both OEM and aftermarket coils, specifically on the passenger's side.

[gramicci101]

Originally Posted by Wonderbar

I don't imagine heat sinks not attached to the coils would do anything, since they are designed to pull heat away from what they are attached to. Aluminum with heat shielding probably is the easiest route.

I had considered that, and put them on the inside surface of the heat shield because the heat is coming from an external source (radiating from the exhaust). Hopefully, most of the heat would be reflected by the heat shield, but once heat soak started to set in, the heat sink on the inside would absorb that as well and spread it over a larger surface area, allowing moving air from the leading edge to dissipate it more effectively. Honestly, it could be floating on standoffs a few mm inside the shield, allowing the resulting air gap between the shield and the sink to help insulate as well.

So the heat sink is not the primary means of reflection/dissipation. The outer, reflective surface of the heat shield is. The heat sink is there as a secondary or tertiary means to absorb and dissipate the heat once it starts soaking through and before it reaches the coils. Considering ATL BRZ's track usage and the fact that he's in Atlanta, I expect that the shield would start to heat soak after a while.

Or it might be entirely unnecessary. But that's why I put it where I did.

Edit: thought of an easier way to word it. The heat sink would be acting to pull and dissipate heat from the shield once the shield got heat soaked. So for the sink, the shield itself is the heat source. I would probably air gap it on small standoffs, to only absorb heat radiating off the inner surface or the shield.

[forwallblakmail]

Originally Posted by romin

I then bought all of the parts and the "special" tools, educated my own mechanic on what needed to be done and he tore it all apart. One of my seals (cylinder one) was completely burned off and the direct injector was so badly pitted that we ended up completely replacing it. I've since bought a second set of four direct injectors so he can quickly swap them once a year and I replace the seals in my spare time.

Did you know that the seal was gone before you pulled the injectors? Like did you have the popping sound? Or what it just the code that made you check them.

I'm thinking I'm going to order 4 injectors here real soon.

[romin]

Originally Posted by forwallblakmail

Did you know that the seal was gone before you pulled the injectors? Like did you have the popping sound? Or what it just the code that made you check them.

I'm thinking I'm going to order 4 injectors here real soon.

After reading the posts here I was pretty sure my seals were gone.
I had the popping noise for about a day or two then I swapped coils and never heard it again. After a friends engine blew up while tracking and the carcuss was found to have a burned seal I started working to get my seals pulled. Two dealerships refused to help so I went to a 3rd party mechanic.

CEL P0351 was the first code followed by some mis-fire codes when the popping noises were occurring. After the coils were replaced my engine ran for about a month on the track with a bad seal and no codes or no popping noises.

Given I've seen my engine run with no codes and bad seals I now pull my injectors once a year and replace the seals just to be sure.

[Kido1986]

What is the 'popping' noise associated with this? Do you hear it from the engine, exhaust? Is it loud?

[romin]

Originally Posted by Kido1986

What is the 'popping' noise associated with this? Do you hear it from the engine, exhaust? Is it loud?

It sounds like a intermittent fire cracker going off in your intake.
The dealership was able to reproduce it by rocking the car back and fourth on a slight slope in first gear.

[ATL BRZ]

Originally Posted by Kido1986

What is the 'popping' noise associated with this? Do you hear it from the engine, exhaust? Is it loud?

Don't mix up the #1 coil going bad and triggering P0351 and DI seals going bad and throwing misfire codes.

They are two separate issues and not correlated as far as I know.


@romin had these two issues back to back which may correlate them to those reading this thread but I'm not convinced that one caused the other. The detonation that leads to DI seal failure is caused by the older factory ECU tunes that didn't have transient ignition retard tables filled in past 5k rpms which allowed detonation between fast high rpm shifts and when the conditions were right (high cylinder temps, questionable octane pump gas)

P0351 and the #1 coil going bad is most likely related to excessive heat breaking it down over time since it's in a spot with lots of radiant exhaust heat and not a lot of air circulation. That's not a proven fact, but there's plenty of supporting evidence in this thread.

[Kido1986]

I didn't think I had this issue, just wasn't sure what to look out for, should this occur.

I definitely agree about the heat. Most of my misfires were in warm situations (repeated hard pulls). Except one. 65 ambient. 55mph cruise control for miles. Drop to third, nail it, shift to fourth. CEL popped at 98mph. I believe I have a relatively up-to-date ECU flash.

Either way, once the #1 was replaced, it hasn't returned. Car has been run HARD many time since. Hoping it stays away

[romin]

Originally Posted by ATL BRZ

Don't mix up the #1 coil going bad and triggering P0351 and DI seals going bad and throwing misfire codes.

They are two separate issues and not correlated as far as I know.


@romin had these two issues back to back which may correlate them to those reading this thread but I'm not convinced that one caused the other. The detonation that leads to DI seal failure is caused by the older factory ECU tunes that didn't have transient ignition retard tables filled in past 5k rpms which allowed detonation between fast high rpm shifts and when the conditions were right (high cylinder temps, questionable octane pump gas)

P0351 and the #1 coil going bad is most likely related to excessive heat breaking it down over time since it's in a spot with lots of radiant exhaust heat and not a lot of air circulation. That's not a proven fact, but there's plenty of supporting evidence in this thread.

The reason I believe they are somehow related is because both are happening primarily on cylinder one. Has anyone lost a coil on cylinder two, three, or four? I've only heard of a couple folks complaining about loosing seals on cylinders other than one and that was second hand knowledge via a dealer. I believe every burned seal photo shown on this forum was from cylinder one.

[ATL BRZ]

Originally Posted by romin

The reason I believe they are somehow related is because both are happening primarily on cylinder one. Has anyone lost a coil on cylinder two, three, or four? I've only heard of a couple folks complaining about loosing seals on cylinders other than one and that was second hand knowledge via a dealer. I believe every burned seal photo shown on this forum was from cylinder one.

Good point; I just don't want owners that get P0351 to read this thread and conclude that their DI seals have failed or will fail as a result. There are many other threads for DI seal failure discussion and the respective misfire DTC's associated with that issue, which is widely agreed upon as a result of a flaw with the early factory ECU calibrations that allows detonation which destroys the DI seals over time.

Excessive heat very well may be a contributing factor to both issues being most commonly centered around cylinder #1, but we just have to be careful asserting that the two issues are correlated until a connection is made and evidence is presented to support it.

[romin]

This is what we need:

http://www.flir.com/flirone/explore/

[ATL BRZ]

We also could probably benefit from coils with heat sinks on them like these, but made for the FA20:



Mojo Performance coil packs, sourced from a GM LSx engine, found in a 2JZ BRZ build thread.

[Yamajee]

Been having this issue for over 6 months now, always ignored it since I barely do anything with the car other than casual driving but, anything WOT and over 6k RPM will set off this CEL and P0351 will always pop up. No popping, no strange sounds, no misfires, no leaks, no nothing, even when CEL is on the car is running just fine and not sluggish or anything, took it to the dealer and they were convinced that they have done what they can and CEL shouldn't come up anymore, 5 minutes later it did and I just ignored them since I know they won't do crap. Can I be convinced that this is an ignition coil faulty and just replace it?