Chrysler Repair: No spark: 2.7L, crankshaft sensor, spark coils

Question
I had a guy put in a rebuilt 2.7 engine he had rebuilt. He has everything in, but says he has no spark. If I remember right, he said he had juice at the coil. He said he put a new crankshaft sensor in. He has been battling his for 4 nights now, could you give me things he should check?  Thanks so much for your help. It has been a nightmre as our firtst mechanic had the car 2 weeks and decided not to do it. Again, thank you

Answer
Happy New Year, Brian!
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Roland

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Hi Brian,
You didn't mention the year of the car or which model, so I can't be sure what to recommend.
Does the mechanic have a code reader to see if any fault codes have been stored in the powertrain controller module memory? If not has he tried the ignition switch approach:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then if this is a '98-on vehicle see if the mileage reading changes to show any 4-digit codes in odometer window. Or if that doesn't work, does the check engine light begin to flash and pause repeatedly. If so count the flashes between each pause and tell me those counts in the order of appearance. The absence of spark in the presence of 12v on the coil while cranking would lead me to see if the cam and crank pulses are also present. There are 3 wires on each sensor: a voltage wire (either 8 (orange) or 5 volt (violet/white) to power the sensor, and then a signal wire (tan/yellow for the cam and gray/black for the crank sensor) and a signal ground wire (black/light blue). With the ignition on, probe between the signal and the signal ground wire of each sensor, while turning the engine over by hand using a socket and ratchet to turn the crank by hand.  Observe for whether there is pulsing of the voltage between 5V and 0.3V several times for each revolution of the crankshaft. That would prove the sensors were good and there should be spark if there is 12v supplied to the individual spark coils when cranking it over with the starter motor.
So that is about the best I can suggest without knowing more about the history and present situation.
Roland

Reply:
The car is a 2001 Stratus. I believe he had a code reader hooked up, but didn't give him any codes. I will forward to him what you suggest and let you know. Thank you very much for your help.

You are welcome, I will await further news from the mechanic