So I have a 2003 BMW 325xi and it keeps dying on me during heavy traffic and it runs rough at idle and some times on the highway when I try to pass someone it doesn’t have any power. It even holds gears sometimes when I drive on the street and highway. I put a code reader on it and it said that I’m running lean and I have misfire on all of the cylinders except 3 and 6. I checked all of my vacuum hoses and ran a smoke test on it and nothing wasn’t damaged or leaking, I’m lost and I need help finding the problem may you please help me. I also checked the spark plugs and coil packs and they are all good.
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i mean lean condi with vacuum leak do not cause power loss but lean condi with low fuel pressure would do it for
thats bad. your scan tool should have maf reading ? are you sure you dont have it ? ok powerloss 1 coil, 2 spark 3 fuel pressure. lean condition shouldnot have power loss, at least in my experience. also there is no way for a simple guys like we are to check coils - it can be tested woth selfmade tool to see how far spark can go, you can check it wherer it arcs or no and you can check it with multimetter but bude coil is a bitch, sometimes it cannot be said without special equipment. also if you moved them bmw has the dumbest dme i have even seen it cannot detect always missfire location.
you still made a good job, now we know you do not have a vacuum leak. in this case you can have low fuel pressure, it is easy to check it.
i think chanses your fuel pressure is low are more then blowen several coils at the same time.
Don’t have that reading. did get a new maf and there was no difference between new and existing MAF.
Your maf reading plz ?
I have a 02 325xi.. i addition to replacing the coil packs (all 6, spark plugs, Valve Cover Gasket, CCV, pulled the manifold off replaced the intake manifold gasket (hard as a rock), replaced the injector seals upper & lower, CCV system (all the rubber hoses) Secondary air hose from the pump to the manifold, the brake booster hose upper & lower intake boot and cleaned the ICV & Fuel pump & fuel filter. Also replaced the entire cooling system and Precat 02 sensors & DISA. It has been flawless for 15k miles after the above. I ran the gas down to a gallon yesterday and the check engine light came of for misfire.. After 200 miles of highway driving after filling up with a full tank the light went away. Everything was original on this car when I first got it.. With each refresh of systems it runs better & better. Sounds like you may have one or several vacuum leaks.. Is the valve cover have a hair line crack in it?. Is the entire CCV in excellent shape? How are the parts above that were changed? Have you checked compression? Checked fuel injectors? Fuel Pump, Fuel Filter?.. Hope this helps.. P.S. post the exact codes it's throwing