My maxima has a random misfire once it hits operating temp my dad has replaced the o2 sensor on the front exhaust bank is there a o2 sensor on the rear/back exhaust bank

 

https://www.my4dsc.com/5thgen-nissan...ion-and-codes/

 

check for oil in the spark plug tubes and mayeb even a coil or coils going bad.

 

There is no oil in the spark plug tubes no leaked of any kind from the I take manifold and no vacuum leaks can anyone help me find out the real problem with this random multiple misfire I have replaced the whole ignition system and it’s still doing this I’m 16 this is my first car and I really need it I really need someone’s help

 

Do a compression and leak down test followed by:

Hitachi ignition coils
OEM NGK spark plugs
Hitachi cam and crank sensors
Verify that injectors are good
No air and vacuums leaks
Check all wires and connectors on ignition coils
Hitachi MAF sensor

 

it runs perfectly fine until it idles when I turned the car off and turned it back on and then it started running rough, and then the check engine light started flashing again my dad‘s friends got most of the throttlebody cleaned. Is there any chance that there’s any cloggage or an issue where the valve is not shutting all the way since this is an idol only

 

You say the CEL flashes.

That being the case, have you checked for DTCs?

 

What are the codes from the CEL.

 

po300 or look at my previous posts

 

start with a power balance to see what cylinder is ACTUALLY missing.

 

With all due respect, the characters P-0-3-0-0 are not included in any of your previous posts.

Best of luck with your address of this issue.

 

what brand are the ignition coils that you are running?

 

If the electronic throttle body plate was moved with the battery connected, you will need to perform a throttle body re-learn procedure. Check the FSM and online for the steps.

It appears that your vehicle is having a major misfire as indicated by the flashing light. Recommend to double check ignition components and only use quality ignition parts such as Hitachi which can be purchased at RockAuto

 

Mine just had one too. Just replaced both valve covers because they were leaking, coils, and plugs and runs great now. Agree check for oil in the coils

 

Per the FSM, when the CEL is flashing while driving, one or more injectors is malfunctioning.

 

incorrect.

flashing CEL is simply considered a catalyst damaging misfire. an injector fault (on the electrical side) would throw a p020x. the ecm has no way to know if theres a mechanical fault in the injector.

 

Don't make me find the page in the FSM and post it.... IIRC, at least for 4th gens where most of knowledge lies, my previous statement is correct. And if I haven't totally remembered this incorrectly, it states that because of the malfunctioning injector issue, continued driving should not commence as it could negatively affect the catalytic converter.

 

Silver is right, flashing misfire doesn't mean it's the injectors. It can be, but doesn't have to be. A very bad coil will cause a flashing cel as well for example.

 

Sorry I haven’t replied in a while, but I do have some updates to my misfire problem. It’s still throwing the PO 300 code and is also giving me a bank two below catalyst threshold code and here’s what I’ve replaced so far I’ve replaced both valve covers and intake manifold gasket brand new OEM Hitachi coil packs new NGK plugs hand soldered on new ignition coil connectors and yes, the wires are soldered correctly it’s not throwing any codes about injectors. I have also replaced the fuel pump and filter yet it’s still runs like crap with the rough idle and misfire. I really need help with this. I am 17. This is my daily driver and I don’t have anything else and about that code earlier about the bank to catalyst below threshold me and my dad are thinking it’s an O2 sensor but don’t know which one if anybody can help me out I would really appreciate the help the Maxima is a GEN 5 1/2 if that helps

 

Which one could be causing my issue

 

I'm starting to think it's time to change injectors on whatever cylinders have a misfire. the only time I have ever seen injectors throw a code is if I forget to connect them.

I've only had 2 cars in the past 26 years that needed an injector changed out and neither threw a code for it. it's rare to see one go bad at all. get a batch from a salvage yard and let them sit in some injector cleaner over night and spray the insides with carb cleaner before installing them. if that doesn't work it might be time for a compression check.

make sure to properly bleed the cooling system, air in the cooling system can make the car run really rich. I've even seen bad wirign on engien coolant temperature sensor make a car run really rich and flood the engien making it stall at idle and hard to restart..

 

I still have my money on it being an injector issue....