NEED HELP 77 280z misfiring

[bryand2]

Hey guys I have a strange issue with my 77, its bone stock and was running fine until i changed the spark plugs, now, when the car is warm and i turn it off then restart it, its only firing on 5 cylinders while idling, as soon as the car is moving and under load it goes away. The car does not do this when cold, but i pulled the plugs and it is running very lean, any ideas?

[EuroDat]

If nothing else was done or changed, I would check the spark plugs. Are they the same as the plugs you replaced or the same type, by this I mean heat range, gap etc? Do you still have the old plugs to complare? You could put them back in and test if it still does it.

Running lean can be caused by a number of things: vacuum leaks, low fuel pressure, resistance in connectors in EFI wiring, clogged injector. If it was running good before you changed the plugs, I would start there before testing other systems in the car.

[SteveJ]

Are you sure you didn't damage any spark plug wires? Are you sure they are seated fully on the plugs? Are you sure you put the right wire on the right plug? Did you use NGK plugs?

[bryand2]

I am using ngk plugs, the old plugs were ngk bpr6es, the new ones were ngk bpr6es-11, which are pre gapped at .044. I did put them back in the correct firing order, and no I did not damage the plug wires. I pulled the new plugs and the tips were white so i thought maybe the -11 gap was too big. Replaced them with the bpr6es and seems to have taken care of the misfire when warm for now...

[bryand2]

I also noticed there was a small amount of oil on plugs

[bryand2]

Ok so the new plugs took care of the problem for the first 2 days but it started misifiring again today when warm. I thought maybe it was the water temp sensor but I dont understand how that would cause a misfire. The other thing that is stumping me is that as soon as the car is under load and moving it goes away. Injector possibly sticking?