Car running rough

The E34 535 was running rough recently. After the car got warm it would not rev past 1500 rpms.

I changed the fuel filter, fuel pump, soft fuel lines, installed a fuel pressure meter, new sparkplug leads, changed sparkplugs, cleaned the ICV with nothing changing the running of the car.

This video was at WOT https://www.youtube.com/watch?v=JB_6STZ8l-A

I went for a drive like this and the car was smoking (out the exhaust) when I got it home.

Today I changed the coolant temperature sensor (blue on on the thermostat) and changed the rotor. The rotor looked damaged (and I had a bosch item from a while ago) and the contact of the distributor I reused whilst using sandpaper on the contacts. There was dust in were the distributor is also.

Attachment 8278

The engine seems to run normal again now.

Rotor is toast! Surprised it started at all. Did you brush as much dust from the cap. sometimes that dust can cause carbon arching and give you a miss or two. Glad you got it sorted though.

Incredible!

It looks like the rotor design causes the copper to burn on that track leading to the distribution contact at the far circumference.

Could it be that something has caused this? Maybe things got bad somewhere (leads/plugs) and the ECU has extended spark dwell and power above normal... ? If it does change dwell, not sure about power though...