In my 98 GXE I have a misfire on #4. Thinking it was the coil, I replaced it and a new plug. That didn't solve the problem. Still have the P0401 and I also have a code P0141 (Oxygen Sensor Heater Circuit Malfunction (Bank 1, Sensor 2) . So I replaced both O2 sensors. it still throws both codes. Does one lead to the other? Or are they a separate issue? Anyway......The misfire is still there. What could I possibly be missing here? Where do I go to in this problem solving dilemma??? Also, what could I be missing with the O2 sensor????
Thanks in advance.

 

Have you tried swapping the plug/coil and fuel injector - one at a time, to a different cylinder to see when the code tells you that the problem has moved to that cylinder ? That will tell you what component is bad, if it is one of those \components ?

 

I'll definitely give that a try.

 

First off do you have the California emissions or federal emissions if your having the os sensors codes and if you have the California emissions you will need to change them all out trust me if they are original and they have not been changed changed them I have the 3.5 02 max and that had the misfire code and the o2 sensors code was up as a multiple misfire changed them all it will fix them all I did that to mine It fixed everything with the car.

 

No I do not!

 

The only thing you haven't tried that it would be is the Fuel Injector. And after 27 years, VERY likely.

Most of us here that are keeping our 4th Gens, replace all 6 injectors with Rebuilt OEM injectors at this stage of the car's life.

LOTSA cheap garbage Wanton Injectors out there so don't be tempted.MotorMan Fuel Injectors has a kit of 6 matched rebuilt OEM injectors for around $130. And you don't have to send your old ones back. Many have used him and I haven't heard any complaints.

It's a bigger job taking everything apart and refreshing the intake system of the engine, but well worth it for another 27 years.

 

I’m in agreement with Keith on the injector replacement.

As an alternative to purchasing new/rebuilt injectors, finding a reputable fuel injection or specialty shop in your area and having your injectors rebuilt and matched locally can be cost effective also.

As far as the coils go, try this … unplug and reconnect each coil pack’s harness connector at least three (3) times. See if this changes anything.

Also, remove each coil boot and fully clean the spring and contact plate/pad that are inside each boot. Either way, at some point, I’d also suggest that you replace (with new) each coil boot. You can purchase new NGK boots for about $5.50/ea.

Lastly, I’d encourage you to replace the camshaft position sensor and both crank shaft position sensors.

That’s my 7 cents …

 

I am going by whats typed on the op thread and as a posted topic that's related to the problem. The malfunction o2 sensor heated circuit shorted thats leaning towards that o2 sensor that sensor is shot and toasted with my experience our cars don't like anything domestic like denso or Bosch one of those 2 are good and 1 is short life and will throw the ses light on shortly after 12 months or 2 years of use also depending on the driving nature and gas you use and put it will put load on the sensor and short its circuit out if its the cheap crap get Ngk o2 or nissan they will last 10-12 years or if it throws and ses light or if your mpg is bad or if your car runs like crap sluggish act. The fuel injector issues can be noted by a crappy start up excessive fuel smells and exhaust backfire or gulping sounds the signs are of this problem are your injectors o-rings and seals are bad and are crap leaking into the engine excessive gas unburned gas can cause cars at start up to choke and hard crank and engine turn overs to much fuel to ignite a spark. Check for these symptoms know than its the injector going south.

 

Yeah, I have troubleshooted everything from cleaning the MAF sensor, to cleaning the fuel system, to (much needed anyway) both O2 sensors. The service manual I have (on CD), doesn't say a whole lot about anything about anything of the car. But I am not sure if it is a ORIGINAL NISSASN manual or not. But I do come in here and read alot, go to YouTube and watch different videos specifically for 4th Gen Maxima's. I do not just take what I see and say it is what I need to do. I research it further and compare.

I do not use anything but OEM parts (If I can find them) other wise I use the next best thing to OEM. I wsill get MotorMan Fuel Injectors kit of 6 matched rebuilt OEM injectors. I thank you for the guideance with this matter . I really am greatful for your help.

 

Did you do this, and what did you conclude ?

 

Well I didn't have the money to actually swap injectors to buy the gas and kit for the intake and all that so I kept on troubleshooting and I did find that the mass air flow sensor have zero resistance and I unplugged it the car around smooth no no misfire of any type so that code disappeared the one that replaced it was the for the MAF sensor that's how I come to test everything from power from the harness power Ball connected to the sensor and then check the sensor for resistance which it didn't have any. So it's been 4 days carquest said that they had one in and they didn't they had to get it from another Warehouse and the warehouse is coming from is Selena wherever that's at but they haven't shipped it yet. Anyway I just replaced this last July and it's still under warranty so it's a warranty exchange when I get it I'll update everyone on any other issues if any of which will hope not. But everything that you guys have mentioned I'm going to keep on keeping all of these replies to my thread and for future reference most definitely. And again thank you for all your help and wisdom as I am still in the learning process. You almost definitely hear from me again somewhere in the 4th generation forum.