| | HELP with misfire issue
I went ahead and just copied the post I put up on Camaro5, in hopes for more opinions.... anyways, please help out if you can.
I am looking for some help with my 2012 ZL1 and hopefully someone can help out. Heres just a generic, quick list of mods, then Ill get to my issue.
102mm TB and ported snout
Nitrous Outlet System
Car was running flawlessly, crisp, responsive ect.... One day about 2 weeks ago, I noticed the car started to feel more sluggish and not as powerful. As a couple days went on, I could feel the car was stumbling and misfiring and not to mention, my wideband now will bottom out on 10.0(PIG RICH) when it used to hover at 11.0-11.2 at all times.... As I have owned many high HP cars, I decided maybe it was time to change the plugs. While I was doing it, I wanted to replace the wires too. Either way, that didnt fix or help the problem.
Completely driving normal like a grandma, its not really too too noticeable but as soon as I remotely put any load on the car, its starts sputtering bad. So at that point, I decided to scan the car while driving under load so I could start my diagnosis. Came up with a crazy cylinder 3 misfire. Just 3-4 seconds of rolling into the throttle, misfire counts hit near 100 on cylinder 3.
So first thing I did was swap coils. Still stayed on cylinder 3 misfire. I then pulled the valve cover to see if maybe a valve spring broke, or maybe atleast one of the dual springs were broken. Visually looks intact. I tried to push down on the spring as hard as possible and couldnt budge it. With that being done, I went ahead and did a compression check and then followed it up with a leakdown. Both passed with flying colors.
Being stumped, I put the car back together, then decided to swap a couple injectors. Put it all back together and the cylinder misfire is STILL on cylinder 3
Please if anyone has any other tricks or opinions, please let me know. Any and all advice is greatly appreciated.