[vapore0n]

I'm currently getting a P0306 code, cylinder 6 misfire. Here is my situation.

Car runs fine. Engine is completely smooth while riding at speed, idle, etc. Some times and only on first start in the morning, the car will jerk a bit, but it settles fairly quick. I think all cars Ive owed have jerked a bit first thing in the morning. After that the car is smooth.

Currently I have 46k miles. I replaced all sparks + coils this Saturday, expecting to fix this issue. Code came back on Sunday.

My course of action. Ill add a bottle of Techron, see if that cleans up the injectors and cylinders a bit. Maybe that is it. Guess the second option is to replace the injector or do a compression test? I just don't want to start replacing things that wont fix the problem.

Any ideas?

C/N: Car gets a P0306 code once a week, even though it runs completely fine

[vapore0n]

Side note.
Yesterday while I was using my Torque app with the car, I noticed that Torque was saying that the O2 bank 2 test failed. Could it be a O2 sensor failing? (prays its just that).

Reading around, most people that have injector problems have gas smell and constant misfire. When I pulled the sparks on Sat, they all looked the same. used, but not abused. No gas smell or anything.

[Andrewah05]

Might be an Injector, were they ever replaced?

[vapore0n]

They have not.
Sad that these cars have these types of problems. Coils and injectors failing so early in its life.

[Andrewah05]

Tell me about it, haven't really experienced coil failures, but 4 out of my 6 injectors have been replaced along with the fuel pump since i took ownership-.-, but yeah most likely and injector or carbon build up

[vapore0n]

Added a bottle of Techron to a full tank of Mobil1 93. Reset the code. Came back yesterday. Ill give it 2 bottles before I take the car somewhere.

So the misfire only happens on cold start. Car starts, stumbles a little, but stabilizes itself and smooths out completely before the exhaust flap even opens. Car rides excellently, no power loss, no issues while riding it hard.

Curious thing. The car has always had this startup stumble. It is just recently that it started showing a code. Recently, as in after the warranty expired
I also had a short in the DMTL pump cables, and this p0306 code only started showing up some time after I got the DMTL code.

I could replace the injector, but dont have the ability to code it in (ridiculous you have to do this). Plus, dont want to replace something that isnt going to fix it.
I think if I take it to the mechanic, a compression test is in order.

[Miller335]

Sell it, buy a lexus or something.

[vapore0n]

Update. Changed injector, problem fixed.

[Andrewah05]

Glad you got it those sneaky injectors!