if its cold, the transmission fluid is thick enough to add some drag to the motor even when in neutral. I can stall my 4cyl when its 10 degrees F or less just by letting the clutch out in neutral. but as for the code, the others are right about it causing hiccups in the idle due to the computer trying to figure everything out while having a bad sensor.
1960 Willys Pickup 226 Super Hurricane T-90 and D18 T/C
1996 XJ SE 2.5L AX-5 and NP241