Battery is strong, cranks strong. I was sure it was vacuum leaks at first and replaced ALL vacuum and heater lines. Bought at dealer because I have a good discount. Double checked all fittings. Did the upper intake gaskets and lines behind motor (m42). Was thorough so I wouldn't have to recheck. This was a progressive issue that took a week of driving to fully manifest itself. Started with a rough idle when cold, but ran fine once warmed. Then cold idle became worse over the week to the point of not being able to hit operating temp. I did notice that under WOT when warm the engine would stumble around 5500rpm and not go past that. I thought fuel delivery and changed pump and filter. Changed that also. Donor coil pack was also put in. Thanks Mtlblue... I'm stumped |