Hi Scotty,

I'm also a Scotty - HAHAHA! Anyway...In regards to my 2004 BMW 320i, manual 5 speed...

I bought a BMW E46 last year that has proven to be an excellent car, after owning an E30 for 10 years that I sold for double what I paid for it (I cringe when you mention a "crap car" and show a picture of a BMW a little bit...yes, they use a lot of plastic in their new cars but they're also still excellent cars if you take care of them)

Anyhoo...

My scan tool used to show a small fluctuation on both banks of the fuel trim, mostly in the negative range of -.78 to -1.56%.

I put in some fuel injector cleaner and for a while I got 0% on Bank 1 and would fluctuate on Bank 2 from -.78%, to 0, to +.78% on the LTFT

Trying to isolate the problem, I swapped the coils on Bank 1 and Bank 2 and on my last highway drive of 200 km I got up to ~+3.56% on Bank 1 and ~+2.25% on Bank 2 at their maximum values.

I will be doing the spark plugs next and also changing the fuel filter which incorporates the pressure regulator in the same unit.

Am I wasting my time trying to get back to 0% on a consistent basis? I know that a few percent is really not an issue, but I learned A LOT working on my E30 and now have the skill and confidence to make my E46 perfect.

Should I sweat over a few percent on the LTFT?

KB