95 7.3l cyl not firing, I need help!!

[brodeur241]

i have a 95 f450 with a 7.3l, the passenger side rear two cylinders wont fire. i changed the valve cover harnesses, and took the injectors out and changed the o-rings. when i pulled out one injector the center o-ring was bad so i thought i found the problem, but they still dont fire. i found the problem buy unplugging the valve cover harness for those cylinders with the engine running with no idle change. every other set works great, just not those two.

[JSchuricht]

Do a buzz test to see if all injectors are firing. Also check for codes, I'm guessing it's a bad IDM.

[brodeur241]

ok, i happen to have a spare one. i'll hook it up tomarrow and see what happens. is it common for it to go? does it usually have that effect on certan cyl. firing when it goes?

[JSchuricht]

It's just an educated guess. With two injectors not firing, it's probably the device firing them or the connection. You already eliminated the under valve cover gasket, so unless somehow the wires for two injectors got cut or the connector was mutilated...

[96F350KID]

On 95 i've seen the engine harness get rubbed through where the post is for the CCV on the driver V/C and rub right through the pass rear injector wires