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If it's an vacuum leak, it will cause the idle to hunt on cold start for a while until it goes to closed-loop. It might affect cold start, but also with drivability problem at the same time. But even after it went into close loop, it will cause the car to lose a bit of throttle response because of lean/unmetered air.
 

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Try this... a fix is to make sure the Crankshaft Position Sensor is pushed all the way into its mounting location (hole) in the block. Most often you will find that the rubber o-ring on the sensor prevents sensor from seating all the way into the block. Should the o-ring present a major problem in trying to seat the sensor, you can get another o-ring or delete it and use an RTV sealant (that can handle the engine temperature) instead. Once the Crankshaft Position Sensor is properly seated the cold start issue should cease.

Technical explanation: When said sensor is not seated properly, the gap between sensor and Reluctor Ring (on crankshaft) is is larger than it should be... this results in a weaker electrical signal to the sensor and; therefore, the signal to the computer that instructs the fuel injectors to operate will be too weak to initiate injector operation and the engine will not start.

Why only when cold? Signal strength from crank sensor is dependent upon two things: 1) the gap between sensor and reluctor ring and 2) how fast (rpm) the reluctor ring is turning. Cold weather causes available battery power to be weaker and motor oil to be thicker... result is lower crank speed (RPM).

This fix was found through weeks of research, a lot of trial and error, and quite an expense (new plugs, wires, coil pack, fuel sending unit, and fuel pressure regulator). Should you be looking for a code on your scanner (or Auto Zones scanner, or Pep Boys scanner....)... not going to happen as a trouble code will only appear if the sensor is bad (open coil); sensor is not bad, it is just not properly seated into the block.
 
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