BMW E30 320i Missfire on no. 5 & 6 cylinder

[RB26DETT]

As in the title guys, theres a 1983 E30 320i for sale near me, theres a missfire in no.5 and 6 cylinder.
Not seen the car yet, but going by the pics it is good, just needs a good polish, only one spot of rust on the rear panel under the light.

Does anyone know the possible cause of the missfire ? I know it could be a multitude of things but whats the most likely culpret ?

Also a rough value on it please, a 1983 BMW 320i 2-door coupe, red, milage is supposed to low, only one spot of rust on it and the missfire, been off the road for a while.

Thanks

[TheInternet]

I'm not aware of any common issues to cause the stated misfire. The worst would be a cracked head / gasket failure, but is possibly just leads/distributor/plugs related. Check them, plugs especially, they can be revealing like opening the skull of a dreaming man.

[RB26DETT]

TheInternet said:

I'm not aware of any common issues to cause the stated misfire. The worst would be a cracked head / gasket failure, but is possibly just leads/distributor/plugs related. Check them, plugs especially, they can be revealing like opening the skull of a dreaming man.

Cheers, I have a spare head here off a 320i so that covers that. Hopefully something simple.

Any idea what its worth ?