P1320 and P0300 - The Dreaded Misfire problem
 

I have a 1999 Maxima SE with 86K miles. I have been having the dreadful misfire problem. Its currently reading P1320 and P0300 (Random/Multiple Cylinder Misfire) I replaced the spark plugs and removed and cleaned the coils about 3 months ago but still no resolution. I tried to isolate the "problem coil(s)" by removing each coil one at a time when the engine was running smoothly and to my surprise the engine stutters when I removed each one of them. Is there a better way to find out which coil is bad? I know eventually I have to replace all of them but right now I am low on $$$. Thanks in advance for your input on this.

You need to disconnect the coils one at a time when the engine is misfiring at idle, not when it is running smoothly. If you disconnect a coil that is functioning properly, the engine should run even rougher. If you disconnect the coil that has the misfiring problem, then there will be little or no change.

I've got the same problem with my wife's 2k Maxima, but the problem is so intermittent that I haven't been able to pinpoint which one is acting up. It never seems to happen with the car in my driveway. In this case you have to wait until the misfiring becomes constant, or nearly so.

I have the misfire problem too but it is only on #1..I changed the coil pack with another one and the problem stayed on #1 so I am guessing maybe injectors or spark plugs for mine. You may try running a bottle of that STP Fuel injector Cleaner through.. Maybe the injectors are getting clogged up?.. I haven't seen the random misfire problem yet but maybe either that inj. cleaner or get a can of seafoam and do the whole 9 yards.. Intake, put a little in oil and run it for a couple days and change the oil, and put some in the gas too to clean some more. I did this on my 240 and worked wonders...

Hope I have helped in some way.lol..or at least I gave a couple ideas..
Mav

You have a 99............. :nervous:
Your best bet is to replace all 6 coils.
I had the dreaded random misfire for about 6 months.
Got a set of used coils and the misfire was gone.
There's really nothing else you can do about it, the 99's are notorious for bad coils.

Where do you suggest getting the used coils? How much should a set of 6 cost?

Thanks everybody for all your responses. I've decided to take a bite and replace all my 6 coils. I'm looking for the mitsubishi brand which aparently has a better seal than the stock Hashin brand. So far I haven't found a deal but I figure that I may need to spend $350-$400. I've searched on ebay but everybody is selling the Hashin brand coils. If anyone knows where i can get a cheaper deal please let me know ...

i've got a 95 that only missfires on very hot days (100+) or under a load. there is no check engine light but i'm hopeing to pull intermitant code soon.
being intermitant under these conditions i dont suspect anything but coil breakdown. i figure at 200,000 miles it wont hurt to changeout the coils with new/quality as i am seeing there tends to be problems in these stock units at 80,000 up.
i guess my question is are there other aftermarket coils out there, such as accel? what source to buy?

I ended up just getting mine at NAPA auto. I think the price was a little better than at Schuck's but the people weren't as friendly. I prefer Schucks or Auto Zone when I am able. I have one of the coil packs for the front (don't know if it is referred to as the left or right) that I don't need. I bought it and one for the back thinking I'd find the bad one, replace it and take the other part back but haven't gotten to taking this part back. Luckily for me the bad one was the first that I tried replacing and didn't have to try each one. They're fairly easy to replace. Even the back ones aren't too bad.

Ok seems I have a similar problem with my 2000 GLE, first time I pulled the codes it read the 5th cylinder (the biggest pain), so I changed out the coilpack with the 1st cylinder and still got an error code on the 5th cylinder. Reset the ECM overnight and now I'm getting P1320 and P0300 (Ignition misfire, and random/multiple misfire. There is a TSB about the wire harness if you have these error codes, but I'm not sure what the best course of action is. Sounds like it's going to be 300+ to change out all 6 coil packs, when the problem might be in the wire harness.

Just a few questions.
1. Any way to further narrow down what my problem might be?
2. If it is the Wire Harness would I need to take it to the dealership and roughly how much is that going to cost?
3. If I do change out all 6 coilpacks, I assume I'll need to go ahead and replace all 6 sparkplugs as well.

I'm new to all this so any help would be appreciated, hopefully I can find a solution that doesn't break me.

Thanks,
JB

I had the same thing on my Honda but it did not have the coils I did plug and wires and I was good.

I would start by fully checking your battery and alternator to make sure your system voltage (should be over 12V at rest, over 9.6V when cranking) is all in-spec because if there is excessive resistance anywhere in the 12V system the coil packs might not be drawing enough power thus offsetting their precision and causing misfires. However, the presence of a TSB on the wiring harness fault makes it a known concern. Personally, I own a 97 and put a lot of (well maintained) miles on her and have never had a problem with any coil packs. I hear the 99's are uncommonly plagued with coil pack failure but I assume the problem persists in 2000's maybe even 2001's. You gotta remember heat is the catalyst in all electrical related mishaps. Heat wears insulation and encourages shorts. If you havent already removed the garbage cardboard insulation plasti-tacked to the underside of your hood I suggest you do so, it will promote air cooling. As for the solution to your problem, I would say, check your battery and charging system and clean any corrosion thouroughly paying special attention to the engine ground which is located on the front cylinder head just below the wiring harness near the fuel injectors. That would be a good time to also take notice of any obviously damaged wires you may see. I don't know your willingness to do this yourself, but if you had an ohmeter you could take out (remove from system) and test each individual coilpack to see if its resistance is within manufacturer's specifications (get it online) and that would identify the culprit coilpack(s). By testing those resistances you'll see if the coilpacks are good. If they are then you are looking at a wiring harness short, and unless you are fluent in wiring diagrams and are unphased by the sight of so many wires that they look like a ball of string, you should hire a skilled professional to pick through and fix the problem ($) or replace the harness ($$$). Good luck!

Ok guys reading these posts and with my own experiences what I want to say is that it's not always the coils. In my case it was the electrical connector that went bad.

Well if doesn't matter how old the thread is people still look for answers and read these. Which is how I found it. Btw I'm not a dude

proof, picture behind the wheel :mardi:

So that's a valid point, however one could open a new thread to discuss the issue and reference the old thread :) That will be indexed and referenced by Google just as effectively!

It's funny because on sites like StackExchange (they've got a little bit of everything!) you can't really "necro" a question. Even something answered in 2008 can have a new answer submitted which helps keep the topic up to date. Yet, the whole mechanic on Stack is entirely different than a forum. If someone answers a question about replacing a water pump (or coding a certain type of function in python) then it becomes the accepted question / answer and it can never be asked again. Duplicate questions get closed.

So, when it comes to forums I typically open a new thread for discussion on a topic, and QA sites like Stack I will append to a pre-existing question or add a new answer.

Either way, welcome to the forums Mickey! I hope that we can all collectively add to the knowledge here :)

Welcome to the forum Mickey. The only Mickey's I knew was Mickey Mantle and that mouse in Anaheim and they were dudes.

Bingo!
 

P1320 is a result to heating and cooling systems, ignition, wire harness and power. Check battery, change coils and spark plugs, check condition of all visible gaskets, hoses and wires.

99s are infamous for bad coils - and I am one to experience it - If there is a bad coil, change all six + plugs. After market isn’t oem but will get rid of rough idle.

p1320 will stay until electric And vacuum issues are resolved.

heres some pics of how I’m trying to solve this..
https://cimg3.ibsrv.net/gimg/maxima....e8bf1c17c.jpeg
https://cimg1.ibsrv.net/gimg/maxima....f70f57468.jpeg
https://cimg2.ibsrv.net/gimg/maxima....050bd7d72.jpeg
https://cimg8.ibsrv.net/gimg/maxima....663b896ff.jpeg
https://cimg9.ibsrv.net/gimg/maxima....c7574163f.jpeg