OK, nearest i can tell, this only seems to happen with 93 octane.

- The car always starts up and runs smoothly when cold.

- When the car has been warmed up and ran for any length of time, then is shut off and sits for like 20 mins-1 hour, when re-starting at least one of the cylinders is not firing, which results in an obviously really lumpy throttle. This lasts for approximately 2 mins, then the cylinder(s) start firing again normally.

I did replace the cap and rotor with generic autopartstore replacements, as well as the wires and plugs, which are Bosch +4s. I hear that people have had problems with the +4s and VGs, as well as not using Nissan original parts in the ignition system, so could any of this be my problem?

Again, as near as i can tell, this problem does not occur on 87 octane gas. Thanks in advance.

 

maybe requires fuel injector cleaning?

 

You mean actually taking out the injectors and cleaning them, or the bottle stuff?

I have used the Gumout super concentrate once or twice since June. No change, really. You think it might be a dying injector then?

 

i cant say for sure its the fuel injector...ive had a similar problem once or twice now...but mine was being caused by the idle air control valve acting up.

 

Try "LUCAS" products. my brother has a 1990 toyota camry and it runs madddddd smooth...dumps lucas in every oil change....they got a whole chain of products.... from oil stabilizers to fuel enjection cleaners to even transmission stabilizers..try sum of that..

 

change the bosch 4s they suck for any car.

 

Put in the correct NGK plug #.
If you don't know it do a search. I've posted it before

 

Thanks for all the help guys. I will look into the NGKs for the time being, though expensive as they are.

 

the VGs plugs are only about $2 ea they are definitely not expensive