Rough on 1st start...still after hours of searching forums!
Here's the background...I'm a used car dealer that specializing in Europeans... I take pride in what I sell and have a 02 325Xit with 128k that's giving me a bit of issue. I know I'm a newbie here but I promise I've read every thread on the subject. So here goes nothing....
1st start of the day...starts right up, idles at about 700ish or so (ambeint temps are about 30-45 these days) but feels like theres a soft miss like one cylinder is misfiring. Here's the catch...after about 40 seconds it's completely gone and will not return throughout the course of driving it during the day.
I've put about 400 miles on it, highway speeds and all and it drives mint! I just know this is not right because I have two other e46's on the lot and they don't do it
There's no active ses light. I've got a computer for BMW's and it has stored misfires 2, 4 and 6.
I originally brought it to my mechanic who's ususally decent with Euro's and they replaced one coil pack. It continued to do the same thing so I brought it to the BMW indie in town and he smoked it, checked fuel pressure, checked for leaking injectors, and looked at all the usual culprits such as intake boots, ccv system, vanos, and all the hoses and connectors, disa, etc.
I don't know where to go from here.
I changed plugs to Bosch+4, all 6 coils, and the valve cover gasket yesterday and there's no difference.