Mis fire problem

[Haydn 0]

What are the common problems for a misfire on a 2.9 OBD1 corrado engine? It runs on 6 nearly all of the time but can suddenly mis fire for around a minute until it jumps back on to 6. It can also start up on 6 or misfiring within minuts between turning the engine off and on.

Anything else apart from Leads, plugs, coil pack, air mass controller, isv?

Any help would be appreciated

Thanks

[gav_113 0]

check all plugs and wires around engine bay, may have broken wire, dirty connection etc? also check earths to engine?