I don't know what engine you had in your '99, but if there is a crank position sensor, then the rpm signal likely comes from there like it did on my 2003 5.4L. I did not need to connect the cam positioner sensor. The Dodge Durango guys need the cam position sensor signal, otherwise the PCM does not believe the engine is running. The Ford PCM produces an error message, but will send the correct signal to the tach.

Here is how I solved the problem: http://www.4btswaps.com/forum/showthread.php?20463

CR

 

it had the v10

what others seem to have had luck with was to take the wire that goes to the tach before it goes into the pcm which is 48 and 85 is the wire that comes in from the cam sensor tie them together before pcm I did that and it doesn't work

I am going to try 2 things now


1 take the ground off and hook it up to the original wire that went to sensor
2 hook up my meter to the sensor and see if I can get a difference in reading if not increase my gap I dont know what the sensing distance is for the sensor I am using

 

update it works!!!!!!

it works

tie 85 and 48 togethere before the pcm hook one wire at sensor and the other wire will go to #85 dark green ground the other wire at sensor

I used the cam sensor from a v10 I think most of them are the same

made a bracket

installed it here is where i messed up I set it at about .040 maybe a little more

I was told it needed to be .018 so I set it to .018 and I have a tach

here is my photo bucket with my bracket and much more stuff


http://s1125.photobucket.com/albums/l582/deck60/ford cummins/

 

Hey deck60, Where did you get the Fummins grill badge? That is nice.

 

that is something that was a combined design here is the guy that helped me and printed it up for me


rasmithdesign@gmail.com
425 885 4329

 

Hey Deck60,

My son and I have a Father/Son project and are trying to do this exact same setup and have read though all of your threads but am still a little unclean on how to do everything. We have a 2001 F-350 that we have put a 1991 12 valve cummins in. We have everything working except the Tach and I agree with you I would rather figure out how to use whats there than buy a Destroked or DCS kit. I do have access to a CNC table so that can taken care of but the wiring is what I am unsure about. If you have a picture or diagram of that it would probably help me.
Thanks for figuring this out.

JB