Took the car ('74 Mav 3.3 200 inline 6) to the shop and the good news is they didn't tell us anything we didn't already know, except that the misfire we knew about was a dead miss. We have ordered brake hoses and plan to take the car back over for them to be replaced and get actual diagnosis on the misfire. The tune up they didn't even charge us for because everything was new and working good. The shop I left it at took two days to look at it. I would have liked them to call or let me know the three times I called that they needed to run tests and just go ahead and do it but after two nights there that's all the info I got... Are there any well known misfire problems with the engine we can fiddle with ourselves?
I would do a compression check and, if that's OK, swap the plug and plug wire for the misfiring cyl with another and see if the misfire moves with the plug & wire. Also check the inside of the distributor cap for burned tracks that indicate shorting. Compression check is simple and easy and just requires an inexpensive compression checker.
how many miles on the engine? was the car running/driving before the miss? how did you discover the miss?
These engines are quite durable and from 74 on, have the hardened valve seats. I suspect bad wires, cap, or spark plug also. I would do what " Jsarnold " suggested. That is the easiest way to eliminate the easy stuff! Do the compression check if the ignition component switch doesn't change which cylinder the miss is on.
