1993 Lincoln Mark VIII

Important note:  I'm using the engine, PCM and EDIS out of this Mark VIII in a restomod 65 Mustang. The engine was running after the swap.  The swap included relocating the PCU and EDIS to the trunk of the car.  This was done by building patch cables using factory connectors on both ends and the original wiring harnesses are still intact.  "like making extension cords to relocate the PCM and EDIS".   The last action taken was cleaning up some of the fuse box wiring that was original to the car. This was also relocated to the trunk.  The engine will crank but not fire.  So far i have rewired the power to both coil packs to bypass the new harness and direct to switched power with 12 gauge wire and a relay.  (a more robust 12V supply).  Here's what I see.  1. the crank sensor signal looks clean on my Tektronix O'scope and shows 234 ohms and 1.5 VAC during cranking.  This is checked at the EDIS and verified directly to the crank sensor in the front of the car.  The EDIS module has 12V power, the crank sensor input is verified,  I get a dirty signal when I look at PIP on the scope.  During cranking if I use an LED and back probe the Coil Packs the LED will drop out during cranking.  Ohms on the primaries and secondaries of both coil packs are within spec.  Grounds on the EDIS all seem to be solid.  Right now I have PIP and SPOUT disconnected and just trying to get it to fire with the EDIS.  I'll add the PCM once that is done.  

Next step will be to run a larger power wire to the EDIS.  I don't see voltage drop at the power inpu on the EDIS (13.4 V - have the battery on a charger full time).  but that's the only step I can think of.  I don't have an amp probe for the coil secondaries but saw a video on using a piece of wire and a bolt and I'm going to try that.  

Any thoughts - again this ran until I did something with power wires from the fuse box.  Power is still coming to EDIS so I'm not sure why that would matter.  Also, I picked up a second EDIS module (used) and have the same results.  Crank, no fire, LED drops out on coil pack during crank.  

One more note - I'll get a backfire or a single pulse just as soon as I let go of the ignition switch.

i've seen where something like that is lack of good ground.

Thanks. I’ll look closer at my ground points. The engine is solidly grounded to the body but the rear of the car which is holding the battery and a ground “bar” may not be grounded well to the body or lower subframe.

Sounds like a cool build. I like the DOHC modular engines, but I honestly forgot there was version with waste spark and and ignition control module.
For what it's worth, I have a picture on my phone of a cranking CMP/CKP capture from my F150 with a single cam 4.6.
I remember from my friends DOHC Fox Body swap that the CMP and CKP is essentially the same on either engine.
The cranking amplitude of the CKP on my 150 is considerably higher than what you are seeing on your engine. 

 

Thanks I have a new crank sensor on the way via eBay. I’ll check the signal on it. If grounding doesn’t work I also ordered a 32 tooth gear and will bench test the EDIS. I’m still suspicious that the long wire runs are creating a problem

The bench test went well. Using the crank sensor and a toothed wheel (with one missing tooth). I can get the coil packs to fire all eight spark plugs. When I put it back on the car and connect to the ECU I get two PIP pulses and then nothing. Testing PIP while cranking show 5 VAC that decays to zero rapidly. The crank sensor tests good on the car and I"ve also tested a new one. Just like I'd expect when the pip signal goes away so does injection pulse - spark is still there.