Yes it should be a direct fit depending on the engines, most 90-93 accords use the f22A1 or f22A4 but either way there should not be any problems.
Yes it does interchange. 1990-1993 Accords have the same camshaft pulley (or cog).
The 1991 is the 4th generation Accord. Most parts on a 1990 to 1993 are interchangeable.
No it will not interchange. You need an Accord transmission from a 1990-1993.
call a HONDA dealer and they will let you know., Else try it for fit.
They are right there on the top of the engine.
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no
The 1990 Honda Accord does not have a cabin filter.
no, 2 different engine blocks, it wont bolt up
Looking at the engine - closest to the driver's side
Engine miss at idle. Can be caused by vacuum leak.
no