Poor Idle

1990 325i convertible
Short History
Broke timing belt, bent valves.
Repaired.

Now it is difficult to crank, spins over fast but just won't catch fire. After a few tries it will fire and rev up fine.
Very weak idle.
But it will idle when cold.

Low power at take off.
At speed it has good power.
After driving a bit it will usually die when I stop at a red light.

A strange thing I found, when idleling cold, if I pull off the oil fill cap, it will go dead.

I figured I got the timing off by one tooth, but I just pulled the front of the motor off and it is dead on.

I have one other thought, but before I pulled the motor apart I didn't hear a vacuum leak.

Any thoughts before I put it back together will be helpful?

check the fuel pressure when running cold and let it warm up with the gauge on.

things im thinking of, fpr or stuck injector, although the oil cap thing is throwing me off

Poor idle/dying when the oil filler cap removed is normal. The crankcase is a closed system. Taking the cap off creates a huge vacuum leak. It would be ABnormal if it didn't affect the idle.

spins over fast but just won't catch fire

lets me believe that your valves are not sealing properly.
Either another mucked-up cylinder repair or your valve adjustment is far too tight

I checked the valve job with the cam out. Head upside down and poured kerosene into the combustion chamber and let it sit. No leaks into exhaust or intake runners.

I'll check the valve lash again this weekend.
My compression tester won't go down into these spark plug cavities, they are way too deep.
But pulling it around with the wrench to get to TDC I can feel each cylinder pumping up.

I'll pass along findings.

Thanks