i just recently bought a 1993 240sx se fastback. It has a constant miss on cylinder2. I thought that the valve cover was leaking making oil cover the plug and boot which would result in misfire. so i replaced both gaskets (spark plug and cover) i cleaned out the head where the plug goes and the plug itself. I also bought all new wires and a plug for cyl2. still a constant miss on 2 (cylinder 2 has never fired since i have owned it)

I pulled the fuel pump relay and cranked it with #2 plug out and i have spark.

I am thinking(and hoping) that i have a clogged fuel injectior. I guess the easy was to figure this out is to swap injectors and see if the miss follows. I hope to god i have compression.l i woukd hate to have to pull the head, but if have to i will.

any thoughts??

 

check wiring connectors too

 

ok so i switched the #1 and #2 injectors and the miss followed to cylinder1. so i was sure that it was an injector. i found one at autozone for $87 so i went to my atm in my misfiring240(probably not a good idea) . when i got back to my car it started without the miss, and it drove all of the way home without it!! it even restarted!! so do you think i still have a faulty injector??

 

maybe the injector wire connector wasn't pluged in all the way???? look at the injector wire connector to see if they are over sized or bent open.

 

actually it was a bad injector, she runs great now!

 

dont be fooled. i have had the same problem in my 92. and it mysteriously fixes itself on the way to being looked at or fixed. it comes and goes.

 

ecu going bad?