What are some possible reasons for it to take more revolutions of the starter to start the engine when cold.

Starter had to turn 4 times over the normal 2 this morning with it being in the 50s, and also could feel some very small stumbling vibrations.

I've cleaned egr passages, iacv, fitv, tb(both sides)

Weak battery?

 

Scratch battery. 12.8 volts

 

Not trying to split hairs here but more trying to get more info to help.

Is it really "slower" revs when the starter is on or is it the "same speed" but longer cranking? Don't get caught up in the numbers here as I'm making them up-another way of asking the same question, normally it cranks over at 300 RPM, but now it is cranking over at 125 RPM's.

 

Slower and more cranks

 

Still might be a weak battery. You probably measured voltage without any load.

Either have someplace like AutoZone test the battery, or measure it under load. Measure voltage at the battery posts, WHILE someone cranks the starter. How low does it drop?