One of the sensors going bad.. forget which O2 ?. '92 and 98 Accords did it after
sitting unused for a month. About a 2000rpm swing even after warmup.

User38221 wrote:
> Sometimes when i startup my 1994 Civic EX (vtec) the engine revs back and forth
> between 1500 and 2000 rpm a few times before finally settling down at 1500
> (then dropping lower as the engine warms up).
>
> anyone know what might be causing this?