misfire problem after having done m20 2.5i sport sport

[E30_rider]

hi all,

recently i just swapped my M20 2.0i to a M20 2.5i sport engine. there seems to be a slight misfire once the engine warms up. did a compression test and was fine. the dizzy cap, rotors, sparkplugs, and coil have been changed but the problem did not go away. plugged in a computer but no code was coming up. took the spark plugs out and the one from cylinder 6 was black compared to the rest, so decided to swap the injector from that cylinder with the one from cylinder 1. took it for a run again and compared the plugs and plug from cylinder 1 was black so this is the next thing il be changing to see if it helps with the misfire. i still have the injectors from the 2.0l engine, does anyone know if these will work on the 2.5sport? is there any difference of the injectors from the 2.0l, 2.5l and the 2.5 sport? or does anyone have ideas if the misfire could be anything else?

also does anyone know where the fuel filter is located?..it is a 88 convertible

[AlpineAde]

RE: injectors, have a look here:

http://users.erols.com/srweiss/tableifc.htm

Just look up your part number for the 2 litre injector and compare it to the standard 325i injector (part number 0-280-150-715).

BTW, there is no difference between engines when comparing the standard 325i and the Sport variant. They are one and the same.

[E30_rider]

iv already swapped the one injectector over with one out of the 2.0 and seems to be running better..but iv compared the part numbers and they are different..the 2.0 injector p/n ends with a 6 instead of 5. on the hunt for a injector now. will there be any lasting damage if i drive with temporary one for now?