Help Troubleshooting Subaru 3.6L

[Ultramaroon]

Originally Posted by Spuds

Lol I did find that in my research into 'wtf are these things called'. Hopefully I can have this finished by next weekend. Need to bring the other automatic car in for some warranty work and there will be hell to pay if we don't have a working car my wife can drive...

I've known that those dampers exist but I've never seen what can happen when they go. Opens up a whole new world for me. Once I read "standing wave" I slapped my forehead, "duh!"

[Spuds]

Nope, that's wasn't it... Still have a cylinder 5 misfire, same symptoms...

Now the question is whether to investigate spark more thoroughly or go after compression. I think the latter might be a take it to someone to fix it kind of thing. Or write it off as dead to me.

[nextcar]

Originally Posted by Spuds

Nope, that's wasn't it... Still have a cylinder 5 misfire, same symptoms...

Now the question is whether to investigate spark more thoroughly or go after compression. I think the latter might be a take it to someone to fix it kind of thing. Or write it off as dead to me.

If you can get to the plugs easily (I am unfamiliar with your vehicle) a compression test is both easy and conclusive... but I would not associate compression issues with your symptoms.

[Spuds]

Originally Posted by nextcar

If you can get to the plugs easily (I am unfamiliar with your vehicle) a compression test is both easy and conclusive... but I would not associate compression issues with your symptoms.

Yeah... It's a Subaru H6. Plugs are not easy to get to. They are, ironically, easier than injectors to get to considering the injectors are on top...

But that is certainly something I can try!

[Ultramaroon]

[Spuds]

Originally Posted by Ultramaroon

Can you guess which one came off the "top" of cylinder#5? Hint, look at the resin.

[Ultramaroon]

Originally Posted by Spuds

Can you guess which one came off the "top" of cylinder#5? Hint, look at the resin.

Is it the one on the right? I wonder if that red dot is thermal paint. An indicator of overheating? WAG


I'm telling ya, Igniters don't last forever. And they can get really sketch for a long time before hard failure. Weak sparks are bizarre animals.

[Spuds]

Originally Posted by Ultramaroon

Is it the one on the right? I wonder if that red dot is thermal paint. An indicator of overheating? WAG


I'm telling ya, Igniters don't last forever. And they can get really sketch for a long time before hard failure. Weak sparks are bizarre animals.

The left one came out of cylinder 5. If you look closely, the resin is cracked.

That being said... Hmmm thermal paint huh. That would be pretty clever

I am discovering that. The weird thing is that the behavior changed so drastically right after I added the fuel line cleaner...

Oh well, here goes something crazy...

[Ultramaroon]

Originally Posted by Spuds

The left one came out of cylinder 5. If you look closely, the resin is cracked.

That being said... Hmmm thermal paint huh. That would be pretty clever

I am discovering that. The weird thing is that the behavior changed so drastically right after I added the fuel line cleaner...

Oh well, here goes something crazy...

Oh, duh! I see it now that I enlarge the pic. NVM my stupid paint idea. Prolly just random pen color for specific QC inspection.

Unless those are a magical stout design, in my experience they're like light bulbs. I've tried to be thrifty on a couple different vehicles and ended up chasing failed ones both times.

[Spuds]

Originally Posted by Ultramaroon

Oh, duh! I see it now that I enlarge the pic. NVM my stupid paint idea. Prolly just random pen color for specific QC inspection.

Change them all. They're like light bulbs.

$80 light bulbs...

[Ultramaroon]

Originally Posted by Spuds

$80 light bulbs...

I know. That's why it took two cars for me to learn my lesson.

[Spuds]

Originally Posted by Ultramaroon

I know. That's why it took two cars for me to learn my lesson.

I think I am going to learn that one the hard way this time lol. Just ordered one last night. Really not sure how long we are going to keep it anyway, the original plan was to trade it in for a smaller CUV-sized car after I got the Buick. Then we had the move. Then we had the pandemic. Then there was clearly something wrong with it...

[Ultramaroon]

Originally Posted by Spuds

I think I am going to learn that one the hard way this time lol. Just ordered one last night. Really not sure how long we are going to keep it anyway, the original plan was to trade it in for a smaller CUV-sized car after I got the Buick. Then we had the move. Then we had the pandemic. Then there was clearly something wrong with it...

I probably still wouldn't follow my own advice but let's necro this thread when the next one pops.

[Spuds]

Replacing coil pack #5 and new spark plugs all around fixed it. For now.

Well, I learned my lesson, always check ALL coil packs when experiencing intermittent misfire.