It's all messed up, JB4 map 2 stock gapped, with intakes only.

[turboAWD]

So it's definitely not fuel, I just had major major misfires and it's weird it's at a partial throttle coming uphill with load. I can almost get it to just continue to misfire at a certain position on the throttle.

Had this exact scenario on my '05 legacy gt on cold starts when < 40-45F - to the point it would stall at a light, run horribly for the first 5 minutes every morning, etc.. Once I revved it up once or twice / warmed it up, went away. No CEL.

It only happened 5-10 times per winter, because CA. I tried adding grounds, etc.

Finally, 3rd or 4th year, got a CEL for misfire and was able to track it down.

Bad coilpack. When a reputable shop installed my turbo / downpope / plugs / etc, somehow they threw on ONE non-oem coilpack. One new OEM coilpack later, all well.

So, to me, sounds like a bad coilpack.

 

[Scott Curry]

Seems crazy to be a coil pack with only 9500 miles on the car. I haven't been able to get it to happen on map 1 or map 0 today, map 2 yes it will pop voom boom. Having the plugs check on Saturday.

 

[turboAWD]

Seems crazy to be a coil pack with only 9500 miles on the car. I haven't been able to get it to happen on map 1 or map 0 today, map 2 yes it will pop voom boom. Having the plugs check on Saturday.

Quality control.. Or, marginally in spec, but got pushed too far with gapped plugs.

Q50s have a problem with blowing factory fuel injectors when tuned according to some people, even though no issues stock..

 

[Scott Curry]

Quality control.. Or, marginally in spec, but got pushed too far with gapped plugs.

Q50s have a problem with blowing factory fuel injectors when tuned according to some people, even though no issues stock..

It would be interesting to find out how many people actually have bad coil packs and maybe make it as an upgrade like the spark plugs just to rule out any possibility of a problem like this which is nearly impossible to track down unless you have another set which also could be bad. So the new set would have to be tested to make sure they exceed the markers for not having issues after being tuned the crying More voltage to pass through them. Ugh

 

[Terry@BMS]

Seems crazy to be a coil pack with only 9500 miles on the car. I haven't been able to get it to happen on map 1 or map 0 today, map 2 yes it will pop voom boom. Having the plugs check on Saturday.

If you run the wrong gap a factory coil can fail after one run. It's a design problem IMHO.

 

[Scott Curry]

So are you saying that it can actually damage the coil and no longer function properly under full throttle with higher boost, whereas the correct properly Gap plugs would have never caused the failure?

 

[Terry@BMS]

Exactly. Most of the time coils don't fail when the plugs fail but sometimes they do. Were any of the plugs you removed cracked? If so I'd swap that coil first to evaluate.

 

[cncBilly]

Had this exact scenario on my '05 legacy gt on cold starts when < 40-45F - to the point it would stall at a light, run horribly for the first 5 minutes every morning, etc.. Once I revved it up once or twice / warmed it up, went away. No CEL.

It only happened 5-10 times per winter, because CA. I tried adding grounds, etc.

Finally, 3rd or 4th year, got a CEL for misfire and was able to track it down.

Bad coilpack. When a reputable shop installed my turbo / downpope / plugs / etc, somehow they threw on ONE non-oem coilpack. One new OEM coilpack later, all well.

So, to me, sounds like a bad coilpack.

My that’s a lot of words to concur.

 

[cncBilly]

Seems crazy to be a coil pack with only 9500 miles on the car. I haven't been able to get it to happen on map 1 or map 0 today, map 2 yes it will pop voom boom. Having the plugs check on Saturday.

Hopefully not the same idiot as last time!

 

[cncBilly]

Exactly. Most of the time coils don't fail when the plugs fail but sometimes they do. Were any of the plugs you removed cracked? If so I'd swap that coil first to evaluate.

Could mishandling of the coil pack during the plug swap/regap possibly cause a problem of this nature?

 

[Terry@BMS]

Could mishandling of the coil pack during the plug swap/regap possibly cause a problem of this nature?

Sure, it's just a piece of electronics. Right now we don't know why they fail so anything is suspect.

 

[cncBilly]

Sure, it's just a piece of electronics. Right now we don't know why they fail so anything is suspect.

Thx. One more quick question if you don’t mind pls. Are coil packs cylinder specific or could a guy buy a spare that could replace anyone that may be faulty? Sailing back ground....we carry spares for freakin everything. Thx you’re a star. Cheers

 

[Terry@BMS]

They are universal

 

[CoconutRob]

Thx. One more quick question if you don’t mind pls. Are coil packs cylinder specific or could a guy buy a spare that could replace anyone that may be faulty? Sailing back ground....we carry spares for freakin everything. Thx you’re a star. Cheers

It looks like ignition coils have different part numbers. Right & left

 

[Terry@BMS]

I stand corrected then. Thought they were all the same.

 

[CoconutRob]

Maybe that could be Scott's problem if installer got them mixed up.

 

[CoconutRob]

I stand corrected then. Thought they were all the same.

This is funny because I was on the Hyundai/ Kia parts site last night they are having a sale. Ordering JB4 soon though I would get a coil to have for spare just in case when I noticed they were different Right to Left.

 

[Terry@BMS]

I'll try to pop one off the left and right later this week to compare them. Maybe the difference is just the mounting bolt alignment?

 

[turboAWD]

My guess is mounting bolt.. In general, they should be swappable in the electronic sense - otherwise, you'd have to have special coding or hardware for ONE coil pack.. That would be weird..

 

[turboAWD]

My that’s a lot of words to concur.

Yeah, I was typing on my phone, while out somewhere. I don't type well on the phone - much prefer a physical keyboard.

Basically, I got horrible stuttering, to the point the car would stall, quite predictably, at anything up to maybe 3/4 throttle. If I kept the throttle there, it would keep stuttering.

If I floored it, once it got past a certain rpm level, it was fine. Maybe Subaru sends extra juice through it at higher RPM, and that was enough to stretch wires slightly due to the to close a gap or something internally. But it strongly reminded me of Scott's symptoms. Once I replaced that coil pack, the issue never came back. And it took FOREVER for the ECU to throw a misfire - not until it had gotten REALLY bad, over the course of several years. I'd forget all about it once things heated up, and then, once things got cold, bam - quite predictably, it would be back. This is the time of year it would happen.