missing cylinder HELP 4.9l 6cyl 88' efi
lonelysoleage27
02-19-2006, 11:19 PM
ok #3 cyl. is a dead miss. I can't figure out why. had injectors out, compression test, fuel pressure test, changed distributor for another that had a newer crankshaft positioning sensor in it. put new platinum plugs in it. the spark plug sparks on the head out of the engine, so it works. it gets fuel on it if u turn the switch back and forth to get engine primed. Vacume tester says late timing but u can't time computerized fuel injection. so i turned distributor to exactly 10degrease before top dead center, still fires right up runs high idle for a minute then calms down to low normal idel. but u try going up a hill and lack of power cause that cyl. is missing cant go over 35mph. driving me nuts please someone help me.:banghead:
mechhound
02-20-2006, 02:27 PM
You say you had the fuel injectors out, did you switch #3 fuel injector with one from a different cylinder to see if the miss stays with #3 cylinder? Anyway I would say the problem would have to be with the injector OR the electrical signal going to the #3 injector, TO FIRE IT OFF SO TO SPEAK, to spray the fuel mixture into the cylinder. Possibly a broken wire going to #3 injector.
lonelysoleage27
02-21-2006, 12:07 PM
You say you had the fuel injectors out, did you switch #3 fuel injector with one from a different cylinder to see if the miss stays with #3 cylinder? Anyway I would say the problem would have to be with the injector OR the electrical signal going to the #3 injector, TO FIRE IT OFF SO TO SPEAK, to spray the fuel mixture into the cylinder. Possibly a broken wire going to #3 injector.
i believe i found the problem. i took the valve cover off last night. i had 3 bent push rods on 3 different cylinders. injector works for sure i changed it and checked for pulsating current. i'll have it back together tonight and let everone know tommorow. thanks for input.
i believe i found the problem. i took the valve cover off last night. i had 3 bent push rods on 3 different cylinders. injector works for sure i changed it and checked for pulsating current. i'll have it back together tonight and let everone know tommorow. thanks for input.
Automotive Network, Inc., Copyright ©2026
