I first encountered this code when i got my car running after supercharger install. I took it to the service road and stomped on it and i saw my MIL lamp flashing and it gave me a solid light after. I went home plugged in my scanner and got no stored codes so i went into pending codes and found the notorious p1399 "misfire at any cylinder". I thought it was the ESM connections which i did not solder yet. So i erased the codes and soldered the connections.

Light never came back on, but i always felt a slight miss at light throttle in 2nd 3rd or 4th either from a light or coasting on the highway and speeding up alittle for a hill. But the light never came on, i came to think it was a bad rear motor mount.

UNTIL Today!!! it was rainy commute going 60 in 6th i applied light throttle to speed up a bit and my car started to stumble alittle and the mil lamp starts to flash again and stays on solid after. I restarted my car and it went away, but i still feel the slight miss at light throttle. sigh* one problem after another after the supercharger )=

What do you guys think it is? ESM is soldered.....
researched it and heard it can be a bad intake Mani gasket? egr? not throwing me those codes..
my esm is still of by a 1/10 of a volt 2.91 ~ 2 2.93 is what its suppsoe to be at...but you guys think that 1/10 of a volt will make my car mis?


just want to get her running good )=

 

do you hear any burbling sound out of your exhausts? high boost or regular pulley? if HB, remove your IMRC

 

Standard Pulley. I dont hear any burbling sounds.
The weird thing is when i boost i dont feel the miss any more.

my AFR at crusing is 14.3-15.8 - 1 when im boosting its at 10~11

 

I'm having the exact same problem right now with my SC and HBP. I had the car tuned with Emanage and left the IMRC plugged in thinking it would be ok. I'm going to unplug it and see if that helps.

 

the weird thing is, you can't even pin point the problem with this code.
some of the guys on the TL side said it could be the coils, plugs or EGR ports as per their experience with this code.

They really stressed the coil and plugs with it not being seated proeprly

 

do a compression test asap then let us know...

 

Will do the compression test right after my finals this week.

Just another thing to think about is; When i just tip the throttle slightly as mentioned earlier; i monitor the wideband and i see that the a/f ratio dips to 16 almost then to 15.3~ then to 14.9 ~15.6 im summary the car is running lean at low speeds. Would this cause the subtle miss in my car? its only really in 2nd or 3rd gear with very light throttle.
But when im boosting or about the boost; shes running way rich: 11 ~ 10 when boosting and about 13~12 at heavy accleration. Its only when im in light throttle. Anyone with a a/f gauge chime in? (= thanks