I’ve been looking for one of these cars for a while. At this time, these cars are the final iteration of the naturally aspirated inline-6 with a manual gearbox and hydraulic steering. So I went looking for a 128i coupe with a manual gearbox. They’re not as common as I had hoped, but one eventually popped up locally on FB Marketplace. Relatively high mileage (170K), engine problems, dead battery. Nothing much out of the ordinary, eh?
This particular one is a pretty early production base model coupe, known internally as the E82 chassis. Mine is Karmesin (crimson red) over an Anthrazit (black) interior. The upholstery is BMW’s vinyl leatherette, known as ‘Sensatec’. I’m pretty impressed with the durability and the feel, it does seem like a decent material. The only installed option is the cold-weather pack, with heated seats and headlight sprayers. Oddly, the build sheet reports that it’s a hot weather version.
I’ve been trying to figure out the rough running problem; this car is equipped with the N52, a 3.0 liter inline 6 that BMW installed in virtually everything. The single-stage intake manifold results in about 200hp. These engines are pretty durable in general but they do have their issues. This one has no problem starting, but it runs incredibly rough. No power, low idle, stalls in short order. The PO claimed it had zero compression in a cylinder. Sounds about right.
I’ve replaced the battery. The car woke up from a long nap in relatively good shape. No major problems, my scanner reported cyl 1-6 misfires, multiple cylinder misfires, and a MAF out of range error. My primary suspicion is a massive vacuum leak, but these motors do have occasional problems with dropped valvetronic springs, cam timing phase errors, and can also have broken bolts in the VANOS drive gears in later versions.
My first repair was the PCV system in the rear of the engine; these kits are available on Amazon for about $20. It’s not really easy to take this apart, but I found that a good sharp 1/2″ wood chisel became my tool of choice. Although the internal diaphragm was indeed split, there was no change. The motor is still barely running.
I pulled the VANOS check solenoids next. They were in decent shape, I tested them with 12VDC. They seemed to work well. I cleaned them & swapped them around. No change, the motor is still barely running.
I’ve invested in a timing kit, along with a new jump pack. This car blew out my old one; it was admittedly several years old. I guess it was time?
Updates will follow!