my car misfires at 90% or more throttle wise abouve 3500 rpms. i had a maf code and rear o2 sensor code and i know the o2 sensor is fine and same with the maf cus i just got one from davesz yesterday. put it on yesterday and cleared the codes but its just the same. what should i do next?

 

how are your spark plugs? I had a horrible miss in mine, did it mostly in second gear under load usually around 3000rpm, i checked my plugs and they were brutal, atleast an .075 thou gap.

 

Same deal here, WOT above 3K RPM, misfires, no codes unless I keep it misfiring. 2 years ago the dealer thought it might be the JWT Popcharger. Just had car tuned up, injectors and TB cleaned and have a new MonsterFlow on the intake and it happened again. Funny thing about what clears it for me is Sunoco 93 and Prestone Fuel Inj Cleaner (Yellow or Gold bottle).

Maybe it's the EGR, don't know but it's been happening off and on for the last 3 years maybe.

 

Weak coil packs will misfire under a load. As your car gets older, the coils will degrade causing the spark to slowly get weaker and misfire, only felt under a load. Your ECU probalby can't detect it yet either. Your best bet is to replace the coils.

Quick note:
Replacing the coils was the best "tune up" I ever did to my car.
The differance in performance at WOT on my 99 was/is awsome.

 

I thought that the coil packs might be an issue, but this first started happening (sporadically under WOT) in 2002, after I changed to JWT and also replaced MAF. Since the problem hasn't gotten worse over the past 4 years, could it still be the CPs? Car was running great under WOT today.

 

well yeah all the symptoms u guys are talking about i get, last night for 10 seconds it was fine. i want to get this fixed fast so where should i get new coils from? i wanna be done with this crap. which coils do you recomend also?

 

Check group deals, there was one for a set for $240 a few months back, I think.

 

Idk but i wouldn't change the coils first, there way to expensive to just try and see if there your problem. I had a similiar problem and i changed my sparks to double-platinum and changed my knock sensor. Fixed my misfire problem and knocking problems. I would spend say 50 instead of 300 first. Just my .02

 

ok i'll try the spark plugs first then. what kind did you use? im really hoping the knock sensor isnt bad, nissan did it last june. only like 13k since then

 

Yes, I've had my problem off and on for 3 (maybe 4) years; until I'm sure it's the CPs, I'm holding off on getting them.

 

im getting coilpacks, i have the same problem im pretty sure that what it is al though no code (Cause its only under load like yall)
i saw a awesome deal on ebay for like 6 for 175. i should have gotten it but i was scurrd.

 

anyone know this problem? need help, I wanted to replace the spark plug cause the last time i replaced it was 4 years ago, at that time i had like 60000miles on it so I replace it with the facotry plug, now the miles is 180000. Now I went out to buy new plugs, want to try those oem laser platuim plug from ngk. they say it is pregaped but I check it anyway and i set it to .044. Now my car is missing at idle like it has a hickup, some time when I floor the gas, I hear poping and some time it even backfired. At highway driving, all is normal. I though it was somthing else was wrong, but I only change the plug and oil change.

 

well today i left for school and didnt make it 100 feet out of the neighborhood. the car had a huge idle lope then would die and couldnt drive it. NO power at all anywhere. i have a spark tester and im gonna try that and see if its the coil packs. my shop teacher said its either the coils, spark plugs or a fuel system thing. i guessed fuel filter, but i know the engine is getting plenty of gas, i can smell it in the exhaust. i'll give an update after i check that after school. anyone know the ohms the coilpacks should be at when working?

 

did you solve this

 

I have an ecu code of 201 only, could it be coil packs

 

ok...used a voltage meter thing. 3 packs are bad. they are hansin or w/e the hell those ones are. im gonna try and clean them and see if that works. im not sure what to use to clean it though. any suggestions?

 

do you mind explaining briefly how you tested them with a voltage meter? cause i tried it but the test seems kinda stupid "if its infinite its good if not, it MIGHt be bad" thats what the haynes manual said and i just didnt trust the test enough to take it seriously.
im considering just replacing all the coils

 

i didnt personally. i brought them to autos to test them myself, but he did it. i dunno what the hell the hell the exact numbers were, but hopefully cleanin the coil and its connections will fix it. i cant this weekend though which blows majorly

 

i have a same problem on mine 99 se ... i got pop charger also .. i can hear it backfiring in my popcharger.. only does it under load or Wide open throtle.. i dont know what the f s deal here.... looks like common problem on 99 maxs.... i think its the coil pack... dont know which one is bad but i am goona take one from my 97 max and keep swaping on each cylinder and test drive it ... when it stops misfring .. i know the coil on that cylinder is bad ... thats what i am gona do i think...i also have no code

 

well my car had little pops at idle, then all of the sudden on day theres an insane idle lope and the car doesnt stay on. it was three coils in a row that were bad, that sucked. and i dont wanna have to pay that insane amount of money to fix it.

 

i recently got a "pop", misfire, or backfire from my short-ram and CEL started blinking so i pulled over opened the hood listened to the engine and found out it was my intake, put stock back on drives even better....but i'm having some other weird problem that kinda seems to be coils but this is at low rpms...what should the volt meter read to check if a coil is bad?

 

im not sure, but i remember some thin like no more than 21 ohms or 22...that makes sense with the numbers i got back from mine. all the good ones were still under 22 ohms

 

ok i got one more question. what number plug should be used? the ones in there are denso iridiums ik20. is that the right kind, not name brand, but the number

 

sdoherty, did you replace your coil packs and did that help

 

I am also getting a CEL. Wwhen i check the code its 201(misfire or ignition problem) I checked all my Ignition Coils they were all 20 to 30 ohms. The how to stated they should be 0 ohms. I kinda think i might have one or more bad ignition coils but im not sure and don't want to shell out $600 till im sure. Any ideas??

 

what brand coils are they?
well ive been at my aunts all weekend and ive been drivin my dads car, so i havent had time to clean the coils and see if that fixes it...im going back today and i'll do that

 

ok cleaned the coils, reset the codes and now it just acts like the maf is bad...i just got one 2 weeks ago from davesz so i dont know what the **** is going on anymore. it doesnt have a misfire at idle anymore though

 

Denso = wrong spark plugs. You should be using NGK spark plugs.

 

whats the review of "Standard ignition" coils? they are 30 bux cheaper than the ones from nissan. should i spend the extra money for the oem ones?

 

I Have The Same Problem And I Changed The Plugs But I'm Also Gettin A 0301 Code And My Car Is Runnin Like Crap.

 

Misfire here too, i was heading home from hockey last night and noticed that the car was running rough, well 10 min. into my drive (on the highway) the CEL starts blinking at me. Car was idling rough around 700 rpms on the way home. got home and checked the ecu code 0604. Gonna go check my coil packs now, anything else to look at?


Edit: Well check my coil packs, switched number 3 and number 5, no dice still getting missfire on number 5 cylinder. So i checked my plug it looks ok, I sanded the contacts just to make them shine, now I am going to run a currency test on the fuel injector for number 5 to see if that turns up anything, then do a test drive to see if that helped anything. ANy other thoughts?

 

I have exactly the same problem, even the same cylinder. Rough below 1.5 k and smooth out above 2k. CEL blinking above 3k. I switched the plugs and still getting the samething. I'm going to check coil packs next. Let me know what you find. Thanks.

 

Same symptoms as me. I tested the coil pack and checked the plug, notta! So I checked the resistance on connector 131 and sure enough the fuel injector is bad. I am going to pick one up tonight at Pep boys for 89.99, but wont have time to put it in until tomorrow night or friday.

 

Wait what exactly are you picking up from pep boys? I replaced my coilpacks with new ones and it seemed to go away but I've only been driving for a couple weeks.

 

yeah I started by checking the coilpacks first since there the easiest to get to and test, but the coilpack tested good. I swapped it with number 3, cleared the code, drove around until the CEL came back, and ran the code again, same thing 0604 (cylinder 5). SO I pulled the plug and checked it, it is less than 15k mi. old and looked good, I cleaned up the connections on it and put it back in. Then tried the resistance test on connector 131 (fuel injectors) mentioned in the FAQ's, got a reading of .011 on injectors 1 and 3, then when I tested number 5 it read like 1.2 to 1.8 and kept bouncing back and forth. So according to the FAQ data, that means it is a bad fuel injector on number 5. I called around and courtesy nissan charges $130, but doesn't have them in stock. Pep boys was the only place that had one in stock and it was 89.99. So I am going to run by there and pick one up, drop it in tomorrow or friday and should be good to go. from what I have read a missfire can have several different causes, so if you are going to fix it yourself you really need to do the work and test each piece of the fuel/spark combination individually as I have, in my case it appears to be the fuel injector, may be different for you.

 

I hear ya.
For some reason I think my problem is something to do with ground wires, I'm gonna resurface them soon