Hey,

First of all, I have a 2002 Maxima. Recently the misfire code on cylinder 3 came on. I bought a brand new ignition coil for cylinder 3 and bought 6 new spark plugs right away and put them on. Car drove ok for 20-25 miles, then the same code for cylinder 3 came on again as well as the code for high voltage 02 sensor rear bank sensor 2. Car started running very rough again.

*For the little while it was running good after the install, I could notice a semi rough idle but nothing to bad.

I have no idea why the code came up again for cylinder 3 and I'm clueless. Can anyone help me out? I appreciate all the info you guys can give me. Thanks, E.


Edit: Also wanted to mention that at highway speeds, 50+, if I try to get on it it bogs for a little bit.

 

might be you injector number 3.

 

I appreciate the help sir! I'm going to do some research on that and see if it's something I can tackle by myself.

 

You might want to swap the new coil with the one on cylinder 1 or 5 to see if the problem moves, just to rule out the "brand new" coil, depending on where where you bought it. (I've heard mixed stories about coils purchased from places like ebay and such). While there, verify that this new coil has a grey dot on top indicating that it is an updated one. Some aftermarket coils have the dots under a silver sticker or something.

 

Ok, I can do that. This was indeed an ebay coil. No dot on top. Thanks!

 

I was (fortunately) getting a few P0302 codes around 74k. I tried swapping a hotter plug since it seemed like there was too much oil deposits on the plug. This seemed to help for a few weeks but ultimately didn't help. Bear in mind that my car never ran rough - only the SES light would indicate something was wrong.

Then I pulled the PCV valve which definitely needed replacing but the codes returned a few weeks later.

I recently replaced the coil (direct from courtesy parts) and (knock wood) that seems to have resolved the problem - 1 month strong so far. I would absolutely suggest changing the PCV as mine was definitely beyond replacing. Hope this helps.

 

I have solved 3 misfires on 3 different maximas, unfortunately once you get one misfire, they tend to multiply. Dealer suggests replacing all six coils ( its a good idea but costs a whole lot) on my own maxima, i have gotten a junk yard set of coils for less than half the price, been working proper ever since. The other two maximas, I told my friends to get oem dealer coils, because there is much less chance of them being bad than the junk yard ones. In my experience, it has never been the injectors or the spark plugs or the harnesses that caused the misfires .Thats my opinion.

 

Yea the aftermarket ones that cost less than oem ones, have a silver sticker on their top that partially says "made in china", they're no good.

 

Well, I went to walmart a few hours ago and bought a bottle of injector cleaner, poured it in my tank and went on a 80 mile trip. It still bogged somewhat when I really got on it at highway speeds but I noticed that gas mileage was unaffected. It definitely wasn't bogging as much as it was before. With my 2002 SE, I'm getting about 23.5 mpg. That's what I've been getting since I bought it about a year ago.

Anyways, tomorrow I'm going to Oreilly's and buying one of their coils that comes with a lifetime warranty and returning the one I bought on ebay. (1 year warranty) They are both the same price anyway. I also plan on changing the fuel filter tomorrow also. (Not that it will help)

To Ajahearn: Thanks for your input. I have to make a trip out to the parts store tomorrow so I may as well pick that up too. Look like it's very cheap anyway.

 

Okay. I think the one I was going to buy had that on top. It's from Oreilly auto and it comes with a lifetime warranty.

 

When I got my cylinder 3 misfire a year ago, I initially replaced just that one and the problem was gone. Later on, I decided to replace the remaining 5. I purchased them from Amazon.com and Autozone and my misfire problem has not come back. I don't remember what the silver stickers say but they are all covering the gray dots on all six coils. In addition to that, they all have the nissan logo and the part number shaved off from the stems and the heads, respectively. So to me, it looks like these are the same nissan "oem's" coils that you can purchase from the dealer at double or triple the price. But that's just me. Some people feel more comfortable buying them from the dealership.

 

Ok, I replaced the fuel filter and I'm not noticing any difference what so ever. I did not to the pcv valve yet though.

I have a question though regarding the misfire on cylinder 3. If the injector for cylinder 3 was bad or going bad, wouldn't it trigger a different code rather than just the p0303 misfire?

Also, I'm still noticing good to excellent fuel mileage. Believe it or not, gas mileage is better now than it was when I didn't have the misfire! The only things I am still noticing is bogging at fast acceleration and it idle's rough under 800rpms. It will dip to 600-700 go back up to 800.

Is it ok to continue to drive with this misfire?

 

nm, found the answer to that..

 

just an update. Turned out the new coil I bought from ebay was the culprit. I put in a used coil and the car runs perfect. I will be getting my money back. What a joke.

 

Thanks for the update. Glad you've got that problem solved. I'll keep staying away from ebay, especially refraining from purchasing electrical parts.

 

No problem. I actually have you to thank. You did tell me to recheck the coil afterall. Anyways, hopefully I get refunded in full. I bought it from the user Global-Automo**ve. They haven't been much help so far, so I may have to open up a paypal dispute..but anyway, thanks again sir!

 

Sorry for bumping an old thread but I'm having a misfire issue with #3 as well. I'm going to order a new set of coil packs from 1AAuto. A set of NGK plugs with this comes to $123.80.

Does this sound like a good idea?

Anything else I should consider?

Anything else I should do or change while I'm in there? Watching youtube it looks like I need to take the intake manifold off to get to the rear packs.

Thanks! You guys are great help.

edit - I'll change the PCV as well.

 

I do not recommend the coils from 1AAuto, you'll be sorry if you do. You need to buy OEM/Hitachi. Like here: https://www.rockauto.com/en/moreinfo...359222&jsn=406 .

 

Cool. I already switched and started filling up a Rock Auto basket. I was going to order the NGK coil packs. Thanks for the recommendation.

(edit) Wow, the OEM's are quite a bit more. I'd like to replace all the coil packs (keeping the good ones as spares). Are NGK coil packs all that bad? I figured if they make good spark plugs... The NGK's are $55 to $60 for a 3 pack. The OEMs $40 to $55 EACH.

The car has about 140K miles, runs great. AC leak and (really cold) start rough idle the two issues. I fill up the AC once at the beginning of summer. The rough idle I'll clean out the throttle bore and idle control valve when I'm doing these coil packs. So what I'm saying is we will be keeping this car for a long time. Always full synthetic oil changes. I don't want to buy bad coil packs and have to change again.

So far I have packs, plugs and PCV in the basket. Air filter is good. Anything else?

Thanks.

 

Not true. The Hitachi coils are $32 each, plus/minus a few cents. Check it out here: https://www.rockauto.com/en/catalog/...tion+coil,7060.

 

Ok, I have 6 Hitachi coils now in the basket, 6 spark plugs and a PCV. Anything else I should get?

I bought the CNC brand MAF and Carb cleaner at Walmart (to fix the cold start issue).

Yesterday I poured a can of Royal Purple Tank Cleaner in and filled up with 11.5 gallons of 93 octane, but it is still misfiring bad (about 50% of the time) that I only drove only a 1/2 mile to the gas station and a 1/2 mile back.

 

Never used an aftermarket MAF sensor. Replaced it with genuine OEM used working MAF sensor. Check all the ignition coil connector. Check the intake manifold for vacuum leak. I highly recommemd Techron Injector Cleaner ONLY.

 

 

Yes, it could. But it also could be the coil, or the coil connector, or the CPS, or the associated connector. You need to follow the diagnostic procedure in the FSM (starts on pg. EC-589) to find out.