Streetka possible misfire EM light going nuts

[Tiggsy]

Other halfs Streetka had the engine light come on and flash at over 40mph - local garage to where she was (visiting family) said their PC said an injector issue.

She drove home and we added injector cleaner to the tank....now (before the cleaner has had a chance to do anything - does that stuff even work???) its missfiring.

Should I drive the thing to get the cleaner flowing round or am i screwing the thing up doing that???