Nissan Repair: 1991 Nissan Maxima, nissan maxima, schrader valve

Question
My car is a 91 Maxima and it well, runs like crap. When it idles and drives it has a terrible misfire. I did a tune up, plugs wires cap and rotor, and it still did it. so I replaced the ignition module and the coil and still it ran just as bad. When I pull the front-middle plug wire off when it is running, it runs just the same. I have been told that its a fuel injector. Is this true? And if it is how hard are they to replace?

Answer
Blake,

It is probably the fuel injectors.  To replace them it is just a matter of disconnecting the battery and venting fuel pressure by removing the gas cap and using a rag to cover the schrader valve on the fuel injector rail.  Then, unbolt the rail and lift the injectors out of the intake.  Remove them from the fuel rail and unplug them.  Use new o-rings and 30 weight motor oil to lubricate the new ones to install them.