losing rest pressure.. (archive)

YO FELLA'S!
My 84 633 is beginning to start hard in the mornings or after it sits for a while. I have to crank the car 2
long times, then on the 3rd attempt, it kind of stumbles then catches. I thought it was the cold start injector because it started leaking a bit. So I replaced it and I still have the problem. Im begining to think its the thermo time switch because I'M noticing that after sitting all night when you start the car in the morning (when its cold) the car would idle high for about 5 minutes till the car warmed up, then the idle would go down to 1000rpms where it normally would be. Now, since this starting problem started when it starts, the car idles rough for a few minutes till it gets warm, then idles normally.
What does this sound like to you guys?

I think it is losing rest pressure and won't start or run properly until the fuel pressure rises to the normal level. Here are some things that could cause this problem:
A leaky injector or cold start valve.
Fuel pressure regulator leaking back to tank.
Fuel pump check valve leaking.
Tiny leak in fuel supply tubing.

I'd swap out the fuel pressure regulator first. Any decent shop could probably find the culprit using a pressure-testing rig (without replacing unncessary parts).

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