I'm having some issues with my car running rough and I'm pretty sure there is an injector problem but I don't know if there is more I need to look at while I have it apart this weekend. The problem started as a slight miss at idle, after I got the transmission rebuilt the car would run rough going up hills but only at 2000 RPM or above, anything below that the car ran smooth. I thought it was a problem with the rebuild but recently the car started running rough between 2000 and 3000 RPM and is running more roughly at idle. However it still runs smooth between ~1000 and 2000 RPM and above 3000 RPM (I haven't had it past 3500 recently). This is regardless of load on the engine (uphill or flat) or speed of the car. I'm figuring there is an injector problem since pulling the sparkplug on cyliner 1 doesn't change anything but I need to pull the manifold off to check the injector. What has me confused is that the car still runs smooth through part of the RPM range, I thought with a bad injector it would run rough throughout the whole range, is there something else I should be looking for also?

 

Ok. The 1st thing you might want to do is to check for ECU codes (see stickies). I think that will be good until the Maxima experts arrives.

 

I can never remember which bank is even, and which is odd... is #1 closest to the headlight, or the mirror?

if it's the front bank, there is a harness on the driver's side of the motor that controls the front three injectors. you can ohm test there, rather than remove the intake.

based on your description, it sounds like a bad injector.

 

The cylinder I'm talking about is on the front bank passenger side, I thought it was #1 but I could be wrong, I do know it's the one under the manifold. I didn't realize there was a harness I could check, I'll look for it. I'm getting the usual gas smell also so I was planning on taking off the manifold to replace the fuel lines connecting the rails but if I can confirm it's an injector problem beforehand I can get an injector and do it all at once, thanks for the suggestion on the harness.

I also had a question on vacuum lines, I replaced most of the lines a few years ago and many of them are really brittle already so I need to replace them when I pull the manifold. I used vacuum line from schucks auto supply, does anyone know if any parts stores carry better vacuum line than others or are they all pretty much the same?

 

Thanks for the tip on the wiring harness, I checked it today and the injector is at 24 ohms so I'm going to go ahead and get the parts to replace the injector and fuel lines all at once.

 

evens towards the radiator. odds toward the firewall. look at your sparky plug wires nuub! that and you wil notice that they are offset so the rear bank (1-3-5) is about 2 inches closer to the timing cover than the front bank (2-4-6)

 

Im having the same problem, thats injector # 6. Its not leaking fuel outside and its not a bad injector, dont waste your money.

 

I checked back on it afterwards, it's actually injector 2 like Caped thought. I know the injector wasn't leaking fuel, the fuel lines were letting vapor out either through tiny cracks or they needed to be tightened, either way I replaced them and there's no more gas smell. The problem with the engine running rough was the injector, I replaced it and it runs great now.

 

im having the same problem and allready have done all that tho????

 

i dont understand at all. but good thing you got yours fixed!

 

I think you might be getting mixed up between a couple threads, you've also been replying on the thread with the guy that has fuel leaking out his exhaust manifold. My problem was completely different than his, the stuff that was wrong with my car are pretty common problems with the third gens, I have no idea what is going on with the other guys car.

 

my car has both of your problems