Injectors. Remove and send them off to be flow tested/cleaned. Or buy a used set and have them sent off to be flowed/cleaned. Will eliminate one of the variables. And is likely the cause of your misfire woes.
997's firing order is 5,3,1 at the top of the crank then 6,2,4 at the bottom. That's too compelling a coincidence to ignore. I still say it's something to do with the crank position sensor or the ignitor chip at the top of the firing order.
I’m sure you sorted this out by now but it sounds like your chain rail guides or tensioners have failed and slack in the chain may have allowed one or more of the cams to be out of time ??
Don't know if you're in the East Bay but the guys at Pacific Power Motorsports in WC are super knowledgeable and may be able to help if you end up needing a shop. They're a Porsche focused shop but I've used them for my F82.
Had same issue with my NSX and it failed smog. I have replaced plugs and coils and it worked fine. Based on my research looks like Catalytic converter can also play a role in misfiring. Some NSX owners have changed their catalytic converters and engine stopped misfiring and passed smog.It is recommended to change all coils and plugs at once.
Actually when I bought the car I had a stock cat swapped on (and ran no mufflers) in order to pass smog. At that time the engine was already misfiring. I'm going to replace fuel injectors this weekend as they seem like the most likely culprit at this point.
@@Zygrene I have a 997 4s and I love the look of it with the gt3 rs kit so I understand how you feel about keeping it, it’s like art in the garage. Worst case scenario, sell the motor and do a k24 turbo swap nick is doing on yt.
Yo LS swap it. You get more power and the engine is lighter. 5.3 of power. No replacement for displacement. U get over 300 horses and the V8 noise sounds wayy more better than the clackity clack of the porsche 6 banger
Time for s2k again
It'll happen sooner or later 🙂
Time for a e92 m3.
Injectors.
Remove and send them off to be flow tested/cleaned.
Or buy a used set and have them sent off to be flowed/cleaned.
Will eliminate one of the variables. And is likely the cause of your misfire woes.
Seems like a ton of fun to work on! 🤣 Time for an LS swap!
997's firing order is 5,3,1 at the top of the crank then 6,2,4 at the bottom. That's too compelling a coincidence to ignore. I still say it's something to do with the crank position sensor or the ignitor chip at the top of the firing order.
Going to look into injectors and CPS if I can rule out spark
I’m sure you sorted this out by now but it sounds like your chain rail guides or tensioners have failed and slack in the chain may have allowed one or more of the cams to be out of time ??
Don't know if you're in the East Bay but the guys at Pacific Power Motorsports in WC are super knowledgeable and may be able to help if you end up needing a shop. They're a Porsche focused shop but I've used them for my F82.
Had same issue with my NSX and it failed smog. I have replaced plugs and coils and it worked fine. Based on my research looks like Catalytic converter can also play a role in misfiring. Some NSX owners have changed their catalytic converters and engine stopped misfiring and passed smog.It is recommended to change all coils and plugs at once.
Keep fighting the good fight
It’ll hopefully be worth it in the end
If I'm still posting depressing IG stories in 2 months send me a rude DM telling me to move on
I heard Caymans are pretty cool
Never put 4 prong spark plugs in a car that it didn’t come with . Not sure if a 997 does or not
Had serious problems with s2k with missfire... ended up being injectors bad
Did u have coolant drop?
You might need to take it to a Porsche specialist.
You have a cat code and did not mention that last time. A bad cat can cause misfires. I would run it open header as a test to see if it feels better.
Actually when I bought the car I had a stock cat swapped on (and ran no mufflers) in order to pass smog. At that time the engine was already misfiring. I'm going to replace fuel injectors this weekend as they seem like the most likely culprit at this point.
@@Zygrene Why not just swap them like you did the coils?
This makes me not want to get a 911 now. Looking into one. Maybe 07-08. 😩😩😩
Get BMW 🤔
Do a compression or a leak down test. I bet the valves are bent from a mis shift or bore scoring.
That’s what mine had. Those motors are susceptible to oil starvation
Compression test came back fine. 200-210 psi across the board
@@Zygrene I have a 997 4s and I love the look of it with the gt3 rs kit so I understand how you feel about keeping it, it’s like art in the garage. Worst case scenario, sell the motor and do a k24 turbo swap nick is doing on yt.
Maybe injectors are getting stuck open from time to time?
It's possible. Going to look into injectors if I can rule out spark
I have those same onitsuka mexico 66s ^_^
I need a new pair!
This thing should be throwing codes at you like an angry girlfriend.
It is. Same misfire 1/3/5 codes popped up today
@@Zygrene Glad you got them. Maybe a bit of lag time to show up as a fault.
Sell it.
I haven't given up just yet!
@@Zygrene I know, I know. I just owned enough german stuff in my lifetime to be officially done with them.
Trade it for a fiesta st
I love RWD too much
Dumb
Lol
Yo LS swap it. You get more power and the engine is lighter. 5.3 of power. No replacement for displacement. U get over 300 horses and the V8 noise sounds wayy more better than the clackity clack of the porsche 6 banger
there is this thing called smog in california.
Yup, blame CARB
The flat 6 is legendary in part for it’s amazing sound first of all, secondly an LS swap costs a ton of money and time and headaches