Bogging/stalling engine start 91 318is

Alright so here is the problem I own and love driving my 1991 BMW 318is but lately the engine has been giving me some slighty serious problems. Whenever I start it it will start fine and idle correctly i will let it sit out of gear and ebrake on for 5-15 seconds then take off the e-brake and put it in first. Now here comes the problem within 100 feet it will not gain any more speed or RPM's no matter the throttle position this goes on for about 10-15 seconds. If it does not stall there, then it will go away and be fine until i start it again. And incase you are wondering yes i have changed all fluids in the car, and the spark plugs. The air filter seems fine and clean. So now it is your turn to try and figure out what is wrong with it. I have been trying to figure this out for about two weeks now (since it started). And don't worry i will know what you are talking I have my ASE certification in multiple areas electical, steering suspension, brakes, and engine performance. Is it possible to be a vacuum leak from the crankcase vent hose? Any ideas will help.

P.S. Is it possible to make adjustments to the
valves it says on our database they are not adjustable but I have not tried yet does any one know. I ask because I have a VERY loud knocking noise coming from the engine. I know this is normal with old BMW's but my friend has the same year and is not nearly that loud mine is audible from inside my house idling.

Thanx
Gearhead202

Hey gear head,
Try plug wires and distributor cap. My old 635 chugged and stalled.
$ 250.00 later at the dealership to correct a fuel switch.

Also have never heard more than a ticking lifter out of the four old BMW's that I have owned. Loud knock could be a main bearing. Good luck.
Schrieber

One more thing about the valve adjustment. If you have an owners manual for your 318 , in the annual check up list it should spell out time between valve adjustments. Good luck.
Schreiber

One more thing about the valve adjustment. If you have an owners manual for your 318 , in the annual check up list it should spell out time between valve adjustments. Good luck.
Schreiber

no i have no such luck i do not have an owners manual but thanx for the advice about the cap and the spark plug wires.