vjsimone Posted August 17, 2020 Share Posted August 17, 2020 not running on two cylinders can only be a few things. No fuel to those cylinders, no compression to those cylinders, no spark to those cylinders, or mechanical failure such as broken rocker arms, bent or broken push rods, or a distributor cap with those two terminals heavily damaged, or the reluctor in your distributor is damaged on those two cylinders and not providing a signal to fire. The TFI module is basically the ignition module that controls the coil it either fires the coil or it doesnt it wouldnt pick and choose I remember a post a few years ago, after hours of trouble shooting a miss, bent push-rods it was, plugs were not wet. Link to comment Share on other sites More sharing options...
vjsimone Posted August 17, 2020 Share Posted August 17, 2020 One of the things I have noticed with my 5.0 EFI Bronco over the years, 34 years, There are two different ignition rotors for that engine, One the parts stores call " The California rotor "( it was also used in New York, New Jersie and one other state). I remember doing a tune up while stationed at Ft Bragg went to the local NAPA and bought cap, rotor, wires, plugs and filters. After the tune up was finished, it ran worse and I want to say that it was missing on 3 & 4. Because I was in NC and nobody asked I ended up with the wrong rotor, the 46 state rotor. After some digging at the NAPA, the finnaly asked if it was from California. They gave me the correct rotor and the miss went away. Are you sure you have the correct rotor? look up your engine calibration number and see if you have the right one. They will both fit, but the Cal. one has a long tail on it with a pin on the bottom of the tail that goes through a hole in the Hallefect sensor cover. The NAPA part number for the" Ca rotor" is MPE FA152SB, the 46 state rotor is MPE FA144SB. Just a thought and a blast from the past. wow, never knew that about the rotors. Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 17, 2020 Share Posted August 17, 2020 I remember a post a few years ago, after hours of trouble shooting a miss, bent push-rods it was, plugs were not wet. Vinny - Are you suggesting he has bent push rods? And, how are you? And where are you? Link to comment Share on other sites More sharing options...
vjsimone Posted August 17, 2020 Share Posted August 17, 2020 Vinny - Are you suggesting he has bent push rods? And, how are you? And where are you? Hello Gary, Well, because of what I read in the thread I was following and throwing in my 2 cent along the way his #8 cylinder had 2 bent push rods. I don't believe they were rattling. He pulled the valve cover for some reason and found the issue. One of those scratch your head threads, because it is easy to work the electrical path, but like Rusty mentions, it can be mechanical. New right knee in the past 3 months. Spent the first quarter of the year fishing along the east coast from Florida to Virginia until my surgery was rescheduled. Scrubbed the Newfoundland visit due to the this plague, well Canada scrubbed it... Link to comment Share on other sites More sharing options...
old55pete Posted August 17, 2020 Share Posted August 17, 2020 wow, never knew that about the rotors. As you can see, I learned about it the hard way. I bought it while stationed at Ft Ord California, took it to Germany and gave it a tune up when I got back and was stationed at Ft Bragg. From that day I remember to tell the parts counter guys that It is from California. Link to comment Share on other sites More sharing options...
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