been boosted for a long time. car has been running good since I revamped the cooling system.

I have about 22k on the car. last rebuild was done in 06... so same tune and plugs since then - hks Fcon Vpro. the other night, under load the car just felt sluggish. would only boost to about 11 psi on spring pressure (usually get to 13 or so). no biggy, been pretty hot lately... then she starts flashing the CEL at me . P0306 (misfire on 6) and the car just feels off. AFRs seem a little lean at high 12s, low 13s but then again, not making much boost,so maybe no big deal. fuel pressure seems normal. knock amp shows no knocks. this is 1/2 through the tank of gas, so don't think it is bad gas

in first and second, car feels pretty much the same. The higher gears she just seems sluggish. I'll get some hesitation as she revs out, but not sure if it is just being on spring pressure or if something else is up. I haven't turned on the boost controller as I don't have it set right.

I haven't had time to really look into this, but my first guess is new plugs, which I have sitting in front of me... second guess is maybe an issue with an injector..... don't think I have a boost leak, and car isn't smoking excessively. an odd concern I have is I recently installed a new stereo and got rid of an elaborate brain/screen setup I have from years go. had to move a lot of stuff around. Didn't unhook anything (that I know of) related to the Fcon... and I test drove the car right after it and it seemed fine. symptoms showed up a few days later.

any thoughts? is my motor going to blow???

 

what about coilpack? you should switch cylinder 6 coilpack to another cylinder and see if the problem follows.

 

good suggestion, though car hasn't had the misfire code in a couple days now..

 

maybe a intermittent bad coilpack.

 

I thought plugs also reading your description. Intermittent boost leak would be a likely culprit also. Couplers age quickly in the engine bay - a small cut/crack would explain the slight drop in boost.

 

13 a/f at 11psi is dangerous. Figure out why you're lean and that will probably fix whatever else as well.

First things first do a compression check on all cyl's to rule out anything sh1tty.

 

Don't think a leak down is going to be my first move right now. Given my fuel pressure seems good, next thing would be an injector(s)?