Dro,

The plan this evening is to first do just what you said. If no results I am going to pull the intake and swap a known good injector (no misfires... Probably number 1) to number 7 since it has been consistently misfiring and see if the misfire follows. I also have capped the Sai plugs in the heads by welding the compression fittings so I'll spray some brake cleaner there to see what happens. Just to make sure I don't have a vacuum leak on any of the four. Finally, while its open I'll check the rockers just to make sure no springs have suddenly taken leave.

I still have all of the tools out so it won't take long. I spend more time looking for tools than anything.

I can also check the compression but if the Rings haven't seated yet I don't expect stellar results there.

I'll post what I find. This engine may just be a lemon and if so I'll put my old 4.0 back in or get something someone else put together.

Edit... Has spark on all cylinders.

 

THe experiment was a success but I just did not like how the engine was running. So I took it out, reassembled my 4.0, and am happily driving around at a slower pace than expected. My fears about the oil pressure were unfounded. There was oil everywhere in the 4.6. In fact I slapped the same front cover and oil pump on my 4.0 and the oil light went out after a few cranks with the spark plugs out.

I also used he same coils, plugs, and wires in the exact same position and I have no misfires. I used the same timing chain and gear. I could go on, but the bottom line is that I didn't like the way it sounded and the mystery misfires, coupled with my oil paranoia, were turning into more of a job than swapping the engine. In fact the swap went very easy... Everything lined up, I cleaned all of the bolts, for some reason I found all of the right sockets and bolts I needed. Nothing broke. Nothing got lost.

So, the 4.6 is on the crane, soon to be on the stand, and when the mood strikes me I'll fiddle with it. The 4.0 is humming like new (which is shocking since it had a little clackity clack before, presumably from old bearings).

Time to clean the driveway.

 

Some times it's better to go with the devil you know, than the devil you don't.
Best of luck with it.

 

Well put, Dro.