86 Spider drivability issues
Normally my 86 Alfa Spider runs like a champ. However, this is the second time where, for some unknown reason, it suddenly idles and runs like crud. It will even backfire through the exhaust
I have a presure gauge temporarily installed. The fuel pressure is a steady 40 psi (rules out fuel delivery issues). It's down to ignition or possibly a sticking valve (or maybe something else that I haven't thought of). Also the pressure takes a very long time to bleed down so I've ruled out leaky injectors.
I disconnected the battery to reset the ecu. No change.
It may also be a sticking exhaust valve. Anyone have any luck with oil additives formulated to free sticking valves?
This first happened about a month ago. I ended up having to nurse the car home. However, the next day it started right up and acted like nothing had ever happened. It ran fine for about three weeks until yesterday.
Any ideas guys?