MISFIRE ON 2,4,6. I HAVE CHECKED DOUBLE CHECKED TIMING. PATHFINDER V6

'93 PATHFINDER XE , VG30E 6 CYLINDER MANUAL

STARTS ON ONLY THREE CYLINDERS 1, 3, AND 5. 2, 4, AND 6 MISFIRE. I'VE TRIPLE CHECKED THE TIMING THINKING ITS THE CAMSHAFT. I'M GOING TO BE DIAGNOSING THE POWER AND CONTROL TO THE FUEL INJECTORS. I'M PRETTY MUCH STUMPED. THE WIRING HARNES I REPLACED WITH A JUNKYARD HARNES FROM AN AUTOMATIC. I'M GUESSING MAYBE IT'S THE HARNESS OR A GROUND FOR THE HARNESS.

I'VE REPLACED VALVES IN THIS CAR AND THE FUEL PUMP IS EL CHEAPO AMAZON DIRECTLY WIRED TO THE BATTERY. THE TIMING I COUNTED THE TEETH EXACTLY 40 BETWEEN THE CAMS AND 43 TO THE CRANK. I'M GONNA CRANK IT AGAIN AND SMELL THE PLUGS TO CONFIRM FUEL ISSUE

Have you checked for a plugged cat?

NO, BUT I DON'T THINK THAT'S THE CAUSE. THE PLUGS ARE BRAND NEW AND THEY ARE COMPLETELY ON 2,4, AND 6.

PLUGS ARE CLEAN ON THAT SIDE 2, 4, 6. I'M THINKING NO FUEL ON THOSE. WILL CONFIRM TONIGHT

Arent cylinders 2,4, and 6 on the same side? but you can check for fuel too thats a variable that can easily be eliminated. normally when i run into fuel issues specifically injectors its normally not one complete side, its one on a certian bank or all of them from tarnish or debris...

EXACTLY! THEY ARE ALL ON THE SAME SIDE. 2, 4, 6 MISFIRING. I JUST THREW EVERYTHING ON AFTER REPLACING VALVES. I'VE TRIPLE CHECKED TIMING BELT WITH MARKS TO SPEC. I WAS FOR SURE IT'S A CAM MISS-TIMED AND I DUNNO WHAT ELSE CAUSED ONE SIDE TO MISFIRE

ok i didnt see your second post where you had changed valves sorry lol..

DONT SMELL GAS ON #2 PLUG. I CRANKED IT AND IT STARTS ON THE 1,3,5 CYLINDERS. BATTERY NEG TO INJECTOR CONNECTOR LIGHTS THE NOID LIGHT. IS IT POSITIVE TO THE SAME SIDE FOR PULSE? ALSO, I DONT HAVE THE EXHAUST MANIFOLD CONNECTED TO THE EXHAUST PIPE SO THERES PROBABLY ROOM TO RELIEVE ANY EXHAUST RESTRICTION

DONT SMELL GAS ON #2 PLUG. I CRANKED IT AND IT STARTS ON THE 1,3,5 CYLINDERS. BATTERY NEG TO INJECTOR CONNECTOR LIGHTS THE NOID LIGHT. IS IT POSITIVE TO THE SAME SIDE FOR PULSE? ALSO, I DONT HAVE THE EXHAUST MANIFOLD CONNECTED TO THE EXHAUST PIPE SO THERES PROBABLY ROOM TO RELIEVE ANY EXHAUST RESTRICTION

Did you check compression?

I CAN HEAR AIR COMING OUT IF I CRANK IT. I BELIEVE THERE IS AIR SPARK. RN IM CHASING FUEL AS THE CAUSE. I DON'T SMELL ANY FUEL ON THE PLUG. STILL NEED TO CONFIRM PULSE TO INJECTORS.

COMPRESSION IS PRESENT. INJECTOR PULS PRESENT

If all 3 cylinders that are misfiring are on the same bank, did you confirm that the spark plug wires didn't end up on the wrong cylinder? I would double check since its quick and easy! I've attached a firing order diagram for you

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

IVE NOW GOT THE CAR RUNNING ON ALL CYLINDERS. I STARTED IT WITHOUT COOLANT AND IT STARTED JUST FINE. I FULLY ADVANCED THE TIMING AND IDLES BOUNCING AROUND 2K RPM. AFTER THE FIRST TIME STARTING THE CAR HAVING IN IDLE FOR A MIN I REVVED IT AND IT STARTED POURING OUT SMOKE. I THINK IT IS BURNING COOLANT WOULD IDLING IT FOR LIKE 2 OR 4 MINUTS BLOW A HEAD GASKET THAT FAST? THERES COOLANT LINES ALL OVER THE INTAKE I WONDER IF ONE OF THEM IS DUMPING COOLANT IN TO THE INTAKE. HOPEFULLY THAT'S WHAT IT IS. I ALREADY DELETED SOME OF THE COOLANT HOSES THAT CONNECT TO THE INTAKE. I DONT HAVE THE HARMONIC BALANCER CONNECTED SO THERE'S NO ALTERNATOR. I TRIED TO START IT BUT IT WAS MISFIRING ON BANK 2 AGAIN DUE TO INSUFFICIENT POWER TO THE PUMP (IM TRYING TO WIRE IT TO THE FUSE BOX)

RESOLUTION

BANK 2 MISFIRE CAUSED ORIGINALLY BY EITHER DISSCONNECTED EGR (MANIFOLD LEAK) OR FRAYED WIRING TO THE O2 SENSOR.

CURRENT CONDITION

WHITE SMOKE - BURNT COOLANT
MISFIRES - NEED TO WIRE THE FUEL PUMP, DOES NOT HAVE A RELIABLE CONNECTION

WHAT HAVE WE LEARNED. MISFIRES CAN BE CAUSED BY VACUUM LEAKS AND AIR INTAKE AND O2 EXHAUST SENSOR.

I NEED TO READ THE ACTUAL SCANNER COURSE

Have you smelled the smoke to confirm it's coolant not fuel?

THANK YOU FOR THE IMPUT ON THE ISSUE. I RAN IT AND PUT MY HAND ON THE EXHAUST WHICH GOT WET AND THERE WAS WATER ON THE FLOOR. I THINK THE ISSUE IS I CRACKED THE LOWER INTAKE MANIFOLD AND THERES A WATER IN PUT THAT GOES INTO THE LOWER INTAKE FROM THE FIREWALL. IM GUESSING IF I BLOCK OFF THE LINE OR REPLACE LOWER INTAKE ( WHICH ILL DO SATURDAY GO TO THE JUNKYARD) IT WILL RESOLVE THE SMOKE