E to I engine swap problems

[Tyler325i]

So this weekend we took an e motor out of a 1986 325e and swapped in a 1989 325i motor, we put in the harness, ecu, maf, flywheel ect., but when we finally got it in and fired it up it is missing on cylinders 3, 4, and 5 and can't figure out what's wrong, I checked the spark and it's good, the spark plugs are good, timing is good, maybe something is wrong with the wiring? I don't have much experience with the e to I swap, just the I motor swap. Any help would be great because I'm stumped.

[jlevie]

Had the engine been sitting a good while w/o being run? If so the injectors on those cylinders could be stuck. You can try tapping them to try to free them. Also check C191 (under the intake) for corrosion of the pins or wires. After that try a new set of ignition wires & distributor.

[Tyler325i]

The motor was running in my friends car like a champ less than a month ago which is probably something I should have stated

[jlevie]

In that case I'd suspect the plugs, wires, and distributor first.

[Tyler325i]

That's exactly what I thought a first