Hey guys , tonight I was leaving work and as I crossed over a rail road crossing my car pretty much kind of lost power a bit . Started sounding like a Subaru and the cel started flashing. I immediately pulled over , cut the car off checked for any leaks and checked my oil . All fine . Started the car up and same thing rough running kinda and same sound from exhaust. Payed an expensive as tow because I was hour from home and do not have triple a or towing in my insurance ( lesson learned ) . Get it home , check the codes and I have these p0311 ( cylinder 1 misfire ) , P0411 Secondary Air Injection System incorrect flow ( not sure if it’s related but once while on my lunch break I started my car and had a cel , inspected some things and a relocated vacuum line from my k&n intake had come loose and cel was gone . Never checked the code but could this possibly be similar ? That line isn’t loose tho ) and the last code is p1399 ? No clue what that is . From talking in a few group chats I’ve come to the conclusion that it’s possibly a coil pack ? I’m at 96k miles and I’m not sure if or when they have been changed or the spark plugs either . The plan is to order some denso coil packs and oem pre gapped spark plugs and replace them all. Just wanted to get all your guys help and thoughts on this thanks !

 

P1399 seems to be a generic random misfire code.
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Try switching the coil packs around and see if the CEL code changes (i.e. instead of cylinder 1 cylinder 2).

 

alright will do , in this process is it alright to start the car at all ? Honestly I only let it run maybe 20 seconds during all this because it just sounded horrible and I didn’t know if I’d damn age anything by letting it run or starting it

 

So you want to clear the codes. Disconnect the battery. Swap the coils. Reconnect the battery. Start it up and let her run. Check codes and see if it differs. Obviously keep track of your coils. If a coul is bad it should be pretty obvious.

And yes a bad coil can make it sound like crap.

 

alright and another question this p0411 code , this came as well. Before this happened I had no cel so how does this relate to the misfire ? Also , this literally happened as I crossed over a bumpy railroad crossing so is it possible something just came loose ? What’s some things I could check for that would cause this that might’ve came loose ?

 

Diagnose the misfire first. The secondary air injection system is partly vacuum based so your misfires may cause it to throw the CEL. Unlike a bad coil, the 2nd air injection is a emissions thing and shouldn't affect drivability all that much.

If you want to check things while you're in there look for loose/cracked vacuum lines but I would figurr out the misfire first before trying to access the 2nd air pump.

 

will do , just ordered 4 Denso Ignition Coils 6732301 and 4 NGK 7772 Spark Plugs which should be here Monday I’ll change out .

 

also real quick , in this whole process of tinkering with things and diagnosing . Starting the car while it’s still misfiring could that cause any sort of damage or anything ? Before I swap things to kind of get a feel ?

 

​​​​​​New coils and plugs can't hurt but I'd diagnose first. That's a lot of change for an internet diagnosis.

 

I’m in a s2k group chat on Instagram , funny enough a guy had the same thing happen to him that same night and pretty much we had the same exact issues as far as what happened and how it sounded . I did have an extra cel but he changed one coil pack on the cylinder the cel read and his issue was resolved . Also , besides injectors I couldn’t see anything else causing this except coil packs and spark plugs unless it’s something much more serious which I couldn’t imagine being the car is somewhat low miles and I treat it alright . I planned on doing spark plugs so I thought just replace them all and I’d rather replace all the coil packs anyway rather then just the one cylinder .