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It's been years, to just learn to drive it. Still, the throttle pedal is so direct, so sensitive on/off it is not right. My second 528i has at least some smooth mush in it to know the difference.

I've disconnected the throttle switches, which is not a solution, but it takes some of the sensitivity out. The linkage bushings are new. Timed correctly.

Is there a place to start ? My plan is to replace components one at a time until it's right. AFM, throttle body, ???, ECU ?

Very strange. Otherwise it runs just fine.

Might be a long shot, but the throttle linkage between the firewall / engine block can be lengthened and shortened through a fair range which could account for too much tension on the pedal. Maybe try adjusting that a little?

Well, this is on my carburetted 528, so I could be way off

Thank you, but it's not the linkage set up, it's the, " Right now !" throttle response. Add pedal, " Now !" Off pedal it'll blow the horn with your nose.

You might think that's a cool race car thing, but it's very annoying. It takes an educated foot and extra monkey business working the clutch pedal to avoid the associated on/off throttle jerkiness.

Technically he is right, if the linkage is somehow messed up it would take very little pedal travel to rev that sucker up.

Or you have a lightweight flywheel...

I'm thinking the afm and ecu. Before I knew much about my car,
I swapped out the afm with one from a 733I. Similar symptoms.
Are your afm and ecu correctly matched?

I have to claim incompetence. The car is a 1981. I rebuilt an engine from a 56,000 mile '80, connecting the '81 ECU wire harness, injectors, and one of the three throttle bodies, AFM's I've managed to collect from previous '79 to '81 528's, 633, 635.

All of which look alike to me, unless there are very subtle part numbers to check go together.

The '79, '80, '81 throttle switches are different from the '78 single switch (harness plug in), and it took awhile to adjust the low end switch to click off at the last possible instant. Earlier was a real off throttle jerk mobile.

The switches work, although disconnecting the off throttle seems to mitigate the sensitive throttle pedal. Not great but better.

As before, my plan is to change out AFM's, throttle bodies, switches one at a time to see if anything works.

Have you swapped distributors? If one curve is different either by design or 30 years, a faster advance curve could create what you are experiencing. Are they the same? Both single or dual diaphragm? Vacuum ports hooked up right? Feel the spring tension on the rotor with it off obviously, do they feel the same? Is idle timing the same assuming 2200 timing is?

+1

Reread my posts about this from years ago. I suggested you check/evaluate the vacuum advance mechanism on the dizzy and told you how to do it.
Best of luck.