[Slow325i]

Hey guys! first post here, Facebook groups are no use , so thought I would try an actual forum.

I have a 2009 325i e92 with N53B30 3.0L engine, that I bought not too long ago off of a friend who got it from Copart and fixed it up, no service history, no contact with previous owner, so not much info about the car at all, but it was a pretty good deal.

So anyway, I took the car to get it remapped, and they told me it has already been remapped but isn't really running right, the print out shows 246hp, and 299nm, however the torque curve is all over the place, and the car doesn't really feel like it has all that much torque low down, but past 3k rpm its seems alright. They also told me that the NOx has been coded out.

I was then told to change spark plugs and come back and they will completely redo the map since they are sure they can make more power out of it once its running better.

So i got an oil and oil filter change, changed the spark plugs and car seemed to run quite a bit better, cylinder 3 and 6 spark plugs were completely black, the car also has 1 single code that I've had since the start of owning it, the code is 3104 - uneven running, stratified charge operation, if I cleared it, it would come back after about an hour of driving, but when I cleared it after doing spark plugs, it didn't come back after a full day, and I'm pretty sure once the code comes on the car doesn't seem to run as well anymore.

PS. also noticed a drop of what I'm guessing is petrol, on cylinder 3 spark plug.. leaking injector?

also when I accelerate the car has a loud hissing noise, sounds like some sort of air leak... so what could be wrong with it? vacuum leak? something with injectors? any help or tips is greatly appreciated, i will be installing a new OEM air filter (replacing the £80 K&N filter that it came with) and fuel filter this weekend, and will be also be putting a full tank of E5 with Petrol Injector cleaner.

Here's the link for the Dyno Print out! the torque curve is terrible.

https://ibb.co/xLHqgJm

Sorry if this was a pain to read, English is not my first language.

[Will_460cs]

see my other posts on this engine... but yes a wet plug left on cold engine will be a leaking injector. the injectors leak after the car is turned off. this normally means they will also flow more fuel and fuel trims will be out of whack. causes lots of issues in the long term.