Hi i recently did an engine swap in my 97 F150 with the 4.6 and now have no spark and no fuel pulse. I believed it to be the crank sensor and have replaced that and still nothing. There is power at both coils at the plug but not at the coils themselves and power to the injectors but when engine is cranking no pulses. I'm lost as to what it could be I beleive I have the grounds correct could it be a pcm issue? My only other concern is when I hook up my scanner to try and read live data as it cranks, soon as I hit the key to turn it over it resets power and the scanner resets(this could be normal on 97 but not sure) any help is greatly appreciated thanks

 

One thing I have seen numerous times after someone has removed the front cover and replaced chains tensioners etc or just removed the pulse wheel. Is that they install the pulse wheel (HDR) back on the crankshaft backwards. If it is backwards it will not align with the crank sensor itself and you will get no pulse.

 

I swapped the motor out of a same year truck and didn't touch any of the internals of the engine

 

I seen your thread and had to make an account on the forum in order to reply, I am in the exact same boat as you are except my motor came out of a 99 crown vic and my truck is a 2000. I cannot get my head around this one, everything checks out but not getting ground signals from pcm to injectors and coils. Hopefully we can be proactive and solve this together.

 

Make sure all your ground connections are tight and clean. Also separate the 40 pin connection between the engine harness and main harness at the firewall. Look for any bent or dislocated pins in both connectors. sometimes a pin will get dislodged and drop down into the housing preventing a connection. Likewise a bent pin will not align with the female with same results. Sounds like a bad connection somewhere. Look for a broken/loose wire at the crankshaft sensor Check fuses as well.

 

after two weeks of troubleshooting and coming up empty handed i was stumped. my crank sensor tested out good but i decided to test it up at the pcm and low and behold i was only getting 0.08 acv. i ran two new wires from pcm to crank sensor and the new engine started up i guess the old harness broke wires being handled and moved around even though great care was taken with it. just thought id throw this out there since i found it very frusterating that there are tons of these "crank no start" threads where no one comes back to tell you if they ever fixed their problem.

 

I think my very last sentence suggested a broken crank sensor wire. Thank you.

 

Yes I tip my hat to you sir, and athank you

 

I have tested every fuse and relay I could find and all have tested good how many volts should the crank sensor wires put out at the pcm?

 

U should get a puslating reading of between .5-1 acv. With mine iwas getting .6-.8 ac volts at the wires by the sensor but up at the pcm only getting .08 which wasnt enough to fire the coils and injectors. Now my harness is randomly failing and ford no longer has harness's available, this is a fun project.... not