P0300 Multiple misfire / sputtering / chocking FIXED!!!! SOLUTION INSIDE
12-17-2012, 07:10 PM
#1
P0300 Multiple misfire / sputtering / chocking FIXED!!!! SOLUTION INSIDE
MUST READ IF YOU ARE HAVING THIS PROBLEM.
So my car had some issues that I starter to take care of a week ago since im selling it.
steering angle sensor - all it needed was a reset.
cam sensor - changed bank2: driver side
now for the random misfire/sputter.. this is a good check list to follow:
I first got the imfamous P0300 code.. which could be so many things!!
1. MAF. dirty or bad- buy the crc MAF cleaner spray from autozone and clean or replace or swap wiht a buddy.
2. CHECK / OR CHANGE SPARK PLUGS.
3. INJECTOR STICKING OPEN? - check spark plugs to see if you find "the black one" if you see a spark plug that absolutely looks different and completely black then the corresponding injectors needs to be replaced.
4. O2 sensors- change if you have any o2 sen codes
5. Clogged cats??-your cats might be cloggedd.. easy way to fix: take out the 2 o2 sensors that plug on to the cats. turn the car on.. if the sputtering/misfire goes away AT IDLE- then your cats are clogged. if you still have misfire at idle then your cats are ok.
6. check coil packs!- easy way to narrow down the culprit is to turn the car on, and while the car is one start disconnecting one coil pack at a time.. if the car dies down or idle changes then that coil pack that you just disconnected is OK. if you disconnect a coil pack and there is no change in the way your engine is running than that is THE PROBLEM!!.
7. vacuum leak? - check intake for vacuum leaks, you can also take off the plenum and check for oil or gas on the intake.
8. PCV valve- change it!! its only $10 on ebay. located on the pass side valve cover.
9. CHECK ALL INJECTOR/COIL PACK CONNECTORS AND HARNESS.
10. MAKE SURE TO CONNECT THE RIGHT CONNECTOR FOR THE COIL PACKS IF YOU DISCONNECT THEM.. CYLINDER 4 AND 6 GET MIXED UP.. CYLINDER 4 CONNECTOR HAS ONE SOLID GRAY WIRE AND CYLINDER 6 HAS ONE GRAY/RED WIRE.
11. bad gas can also lead to misfire.. and so can a clogged fuel filter..
MY PROBLEM ENDED UP BEING A BAD COIL PACK. AFTER I CHANGED ALL 6 INJECTORS AND NEW MAF, I RESET THE ECU (http://www.technosquareinc.com/350reset.htm) AND TOOK IT TO AUTOZONE TO GET THE CODES PULLED AGAIN.. FINALLY GOT P0301 WHICH NARROWED DOWN TO CYLINDER #1.. REPLACED THE COIL AND BAM!! CAR WORKS LIKE A CHARM. HERE'S THE VQ35DE CYLINDER ORDER ALSO.. AND THIS WEBSITE IS HELPFUL IN FINDING OUT WHAT THE CODES MEAN (http://nissanhelp.com/index.php)
THIS WAS A HEADACHE FOR ME AND JUST HOPE I CAN HELP OTHERS.. ALL THIS INFO WAS GATHERED FROM THIS FORUM, FROM DIFFERENT POSTS.
So my car had some issues that I starter to take care of a week ago since im selling it.
steering angle sensor - all it needed was a reset.
cam sensor - changed bank2: driver side
now for the random misfire/sputter.. this is a good check list to follow:
I first got the imfamous P0300 code.. which could be so many things!!
1. MAF. dirty or bad- buy the crc MAF cleaner spray from autozone and clean or replace or swap wiht a buddy.
2. CHECK / OR CHANGE SPARK PLUGS.
3. INJECTOR STICKING OPEN? - check spark plugs to see if you find "the black one" if you see a spark plug that absolutely looks different and completely black then the corresponding injectors needs to be replaced.
4. O2 sensors- change if you have any o2 sen codes
5. Clogged cats??-your cats might be cloggedd.. easy way to fix: take out the 2 o2 sensors that plug on to the cats. turn the car on.. if the sputtering/misfire goes away AT IDLE- then your cats are clogged. if you still have misfire at idle then your cats are ok.
6. check coil packs!- easy way to narrow down the culprit is to turn the car on, and while the car is one start disconnecting one coil pack at a time.. if the car dies down or idle changes then that coil pack that you just disconnected is OK. if you disconnect a coil pack and there is no change in the way your engine is running than that is THE PROBLEM!!.
7. vacuum leak? - check intake for vacuum leaks, you can also take off the plenum and check for oil or gas on the intake.
8. PCV valve- change it!! its only $10 on ebay. located on the pass side valve cover.
9. CHECK ALL INJECTOR/COIL PACK CONNECTORS AND HARNESS.
10. MAKE SURE TO CONNECT THE RIGHT CONNECTOR FOR THE COIL PACKS IF YOU DISCONNECT THEM.. CYLINDER 4 AND 6 GET MIXED UP.. CYLINDER 4 CONNECTOR HAS ONE SOLID GRAY WIRE AND CYLINDER 6 HAS ONE GRAY/RED WIRE.
11. bad gas can also lead to misfire.. and so can a clogged fuel filter..
MY PROBLEM ENDED UP BEING A BAD COIL PACK. AFTER I CHANGED ALL 6 INJECTORS AND NEW MAF, I RESET THE ECU (http://www.technosquareinc.com/350reset.htm) AND TOOK IT TO AUTOZONE TO GET THE CODES PULLED AGAIN.. FINALLY GOT P0301 WHICH NARROWED DOWN TO CYLINDER #1.. REPLACED THE COIL AND BAM!! CAR WORKS LIKE A CHARM. HERE'S THE VQ35DE CYLINDER ORDER ALSO.. AND THIS WEBSITE IS HELPFUL IN FINDING OUT WHAT THE CODES MEAN (http://nissanhelp.com/index.php)
THIS WAS A HEADACHE FOR ME AND JUST HOPE I CAN HELP OTHERS.. ALL THIS INFO WAS GATHERED FROM THIS FORUM, FROM DIFFERENT POSTS.
Last edited by boostintt; 12-17-2012 at 07:12 PM.
The following users liked this post:
RobPhoboS (04-15-2016)
12-28-2013, 02:59 PM
#2
Registered User
Join Date: Dec 2013
Location: Cape Town, South Africa
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
Hi guys, new to the site. This tread saved me a lot of cash, thanks dude!!!! 
I changed my spark plugs on +-80 000Miles (130 000km in South Africa) as I haven't had the car long after I bought it second hand. After I drove it for about 5 minutes I realized that something's not right. NO EML / WARNING LIGHTS came on!!! WTH!!!
After checking out whats up, I found Cylinder 4 and 6 's ignition coils not making a difference when unplugging with the engine running. Checked on the service manual what the specs are in resistance and tested the coils. Getting of the readings got me a bit confused. The instructions in the manual are fuzzy... So "without pictures" test it like this
--->WHEN looking at the 3 pin coil in your hand the PLUG LOCATING BLADES face to the TOP. The pin nr's are then '3 2 1' working from the left.
MEASURE the left pin(3) and the center pin(2) = average of about 1,5 OHM.
(((I recon if its more than 1,9 OHM it may be going or is already gone)))
After reading this tread it dawned on me...
(Background) I'm a real perfectionist and feel that a clean engine outside helps an engines operation inside (Why else would 90% of vehicles coming in with major damages be dirty???) When everything was off, I cleaned it all, focusing mainly on the tappet covers. My 6th cylinder tappet cover spark plug tube seal was leaking as well, so I REALLY got in there when I cleaned.
So my MISFIRE was CAUSED by MIXING up the coil PLUGS ONTO the coils at cylinder 4 and 6 (the rear ones on the left 'wheel' side).
They really did a bad job when they designed the wiring.... Too short here, too long there... "Why split the wiring loom? We can just let it run all around on top of the hot parts" I work for Subaru and it's the same nonsense....
It's almost 2am here, so excuse if I ramble.... :P
I changed my spark plugs on +-80 000Miles (130 000km in South Africa) as I haven't had the car long after I bought it second hand. After I drove it for about 5 minutes I realized that something's not right. NO EML / WARNING LIGHTS came on!!! WTH!!!
After checking out whats up, I found Cylinder 4 and 6 's ignition coils not making a difference when unplugging with the engine running. Checked on the service manual what the specs are in resistance and tested the coils. Getting of the readings got me a bit confused. The instructions in the manual are fuzzy... So "without pictures" test it like this
--->WHEN looking at the 3 pin coil in your hand the PLUG LOCATING BLADES face to the TOP. The pin nr's are then '3 2 1' working from the left.
MEASURE the left pin(3) and the center pin(2) = average of about 1,5 OHM.
(((I recon if its more than 1,9 OHM it may be going or is already gone)))
After reading this tread it dawned on me...
(Background) I'm a real perfectionist and feel that a clean engine outside helps an engines operation inside (Why else would 90% of vehicles coming in with major damages be dirty???) When everything was off, I cleaned it all, focusing mainly on the tappet covers. My 6th cylinder tappet cover spark plug tube seal was leaking as well, so I REALLY got in there when I cleaned.
So my MISFIRE was CAUSED by MIXING up the coil PLUGS ONTO the coils at cylinder 4 and 6 (the rear ones on the left 'wheel' side).
They really did a bad job when they designed the wiring.... Too short here, too long there... "Why split the wiring loom? We can just let it run all around on top of the hot parts" I work for Subaru and it's the same nonsense....
It's almost 2am here, so excuse if I ramble.... :P
12-29-2013, 04:46 PM
#5
Registered User
What kind of cheap scan tool are you using? Do you even know how to interpret live data from O2 sensors? What should a healthy upstream sensor be doing? What should a healthy downstream sensor be doing?
Trending Topics
12-31-2013, 05:05 AM
#9
Registered User
12-31-2013, 05:15 AM
#10
Registered User
Here's something I found just for you Spike. This explains why dry gas is important, for those of you who must run 10% ethanol. I found a much better article somewhere else, but couldn't copy it.
The problem with gasoline/ethanol blends include phase separation, which happens when the ethanol (which is hygroscopic, meaning it has an affinity for water) has absorbed enough atmospheric moisture to fall out of suspension with the gasoline. We’re told the precise amount of water required to affect this separation depends on temperature. At 60° F, it’s said to take just .45% water to create separation, slightly more at higher temperatures and even less at lower temperatures. Exposure to a breeze will also accelerate water condensation, as the ethanol will chill the fuel container, creating beads of water on its walls
The problem with gasoline/ethanol blends include phase separation, which happens when the ethanol (which is hygroscopic, meaning it has an affinity for water) has absorbed enough atmospheric moisture to fall out of suspension with the gasoline. We’re told the precise amount of water required to affect this separation depends on temperature. At 60° F, it’s said to take just .45% water to create separation, slightly more at higher temperatures and even less at lower temperatures. Exposure to a breeze will also accelerate water condensation, as the ethanol will chill the fuel container, creating beads of water on its walls
Last edited by myfirstzcar; 12-31-2013 at 05:22 AM.
12-31-2013, 12:18 PM
#11
New Member
Thanks for the information. I appreciate your research.
Minnesota researchers are very protective when revealing statistics for ethanol-additions to gasoline, and they claim there is a very low possibility of condensation. Although I believe your facts, I must admit never experiencing any problem using ethanol blended gas in my 350z (for 10 years now, since 2003).
The same was not true when Minnesota required soybean/diesel blending. My diesel vehicle became “waterlogged” and would not run with this fuel. I wasn’t the only one. The school districts couldn’t keep their diesel bus-fleets on the road when blending soybeans with diesel. Mercifully this has gone away because it is no longer economically practical.
--Spike
Minnesota researchers are very protective when revealing statistics for ethanol-additions to gasoline, and they claim there is a very low possibility of condensation. Although I believe your facts, I must admit never experiencing any problem using ethanol blended gas in my 350z (for 10 years now, since 2003).
The same was not true when Minnesota required soybean/diesel blending. My diesel vehicle became “waterlogged” and would not run with this fuel. I wasn’t the only one. The school districts couldn’t keep their diesel bus-fleets on the road when blending soybeans with diesel. Mercifully this has gone away because it is no longer economically practical.
--Spike
Here's something I found just for you Spike. This explains why dry gas is important, for those of you who must run 10% ethanol. I found a much better article somewhere else, but couldn't copy it.
The problem with gasoline/ethanol blends include phase separation, which happens when the ethanol (which is hygroscopic, meaning it has an affinity for water) has absorbed enough atmospheric moisture to fall out of suspension with the gasoline. We’re told the precise amount of water required to affect this separation depends on temperature. At 60° F, it’s said to take just .45% water to create separation, slightly more at higher temperatures and even less at lower temperatures. Exposure to a breeze will also accelerate water condensation, as the ethanol will chill the fuel container, creating beads of water on its walls
The problem with gasoline/ethanol blends include phase separation, which happens when the ethanol (which is hygroscopic, meaning it has an affinity for water) has absorbed enough atmospheric moisture to fall out of suspension with the gasoline. We’re told the precise amount of water required to affect this separation depends on temperature. At 60° F, it’s said to take just .45% water to create separation, slightly more at higher temperatures and even less at lower temperatures. Exposure to a breeze will also accelerate water condensation, as the ethanol will chill the fuel container, creating beads of water on its walls
They are both alcohols.
01-01-2014, 02:55 AM
#13
Registered User
I don't know much about e-10, but I do know it separates in a matter of a couple months. I do know that it won't harm anything if it gets used and isn't allowed to separate.
What you ^ don't know is that water can appear in any fuel tank, be it gas, any ethanol blend, or diesel. When enough of it gets in there, it can freeze and cause fuel starvation. You say you live in frostbite falls, how the hell do you not know what freakin' dry gas is?
What you ^ don't know is that water can appear in any fuel tank, be it gas, any ethanol blend, or diesel. When enough of it gets in there, it can freeze and cause fuel starvation. You say you live in frostbite falls, how the hell do you not know what freakin' dry gas is?
01-01-2014, 05:36 AM
#14
New Member
^^ In the 1960’s and 70’s I kept my tank full in the winter and used a product called “Heet” in my gasoline. I think it was methanol. My cars would freeze up without it.
Minnesota was blending ethanol and gas by the 1980’s and I found that I didn’t need any winter additives to prevent freezing in the fuel lines. I haven’t used any additives for years now.
--Spike
Minnesota was blending ethanol and gas by the 1980’s and I found that I didn’t need any winter additives to prevent freezing in the fuel lines. I haven’t used any additives for years now.
--Spike
12-24-2015, 01:41 AM
#16
Registered User
I have the same issue (P0300) but it is intermittent. I can go 100+ miles without having a misfire (P0300), and other times I can't drive 3 miles without the issue occurring. If I idle for a bit, it usually goes away, and I have driven in all different weather and temps and the issue occurs the same in all conditions. I have never gotten a specific cylinder code, only the random/multiple misfire code.
As of now I have no idea what is causing it. I pulled all of the coil packs and tested the resistance. All fell between 1.3 and 1.4. Put in some dry gas and the issue was still occurring. I used the gas and filled up again, and the problem is still occurring intermittently. I have also cleaned the MAF and that didn't change anything. I may try a new one, just in case.
I plan to start checking/changing the above described resolutions, but wanted to post this now in case there are others that have the same issue. Ill post an update when I resolve the issue, and what it was that caused it.
Whats driving me crazy is how intermittent it is. I can go days without it, but some days it won't go away.
Any suggestions are welcomed, but as I said I'm going to begin to check the above resolutions.
As of now I have no idea what is causing it. I pulled all of the coil packs and tested the resistance. All fell between 1.3 and 1.4. Put in some dry gas and the issue was still occurring. I used the gas and filled up again, and the problem is still occurring intermittently. I have also cleaned the MAF and that didn't change anything. I may try a new one, just in case.
I plan to start checking/changing the above described resolutions, but wanted to post this now in case there are others that have the same issue. Ill post an update when I resolve the issue, and what it was that caused it.
Whats driving me crazy is how intermittent it is. I can go days without it, but some days it won't go away.
Any suggestions are welcomed, but as I said I'm going to begin to check the above resolutions.
12-24-2015, 04:59 PM
#17
New Member
I had a similar problem, except for the degree of intermittency you describe. I could go for a day or two without a problem, and then I would experience the intermittent misfire.
My problem was the coil packs.
My problem was the coil packs.
12-24-2015, 06:17 PM
#18
Registered User
I plan to experiment a bit more with the coil packs, but I'm starting to believe the MAF may be to blame. When I took the coil packs out I cleaned the MAF while I was in there, and the issue was occurring less often, but has now begun to occur more often again (about 300 miles later). I believe that maybe the MAF is nearing its end. Ill update with any news, and especially when I resolve the issue
******UPDATE 03/29/2016******
I changed the coil packs, and the spark plugs.
AND GUESS WHAT!?!?
My Z is still misfiring
I'm going to replace the PCV valve, and MAF next, as well as check for a clogged cat by using the o2 sensor test as OP described.
Last edited by RichPow; 03-29-2016 at 03:01 PM. Reason: Update
04-14-2016, 10:45 PM
#19
Registered User
So i replaced the PCV valve and MAF sensor and I still have the misfire, NO CODE!!
Im interested if anyone has any other ideas before I check the cats with the 02 sensor trick, and also before I go further and test/take out the injectors for closer inspection.
I have attached a video (link) to show what it sounds like at idle. If you can't hear it I can redo it with my camera rather than my phone, jut let me know.
*listen carefully*
As always, thanks for the info!
Video: https://www.youtube.com/watch?v=_BdT...ature=youtu.be
https://www.youtube.com/watch?v=_BdT...ature=youtu.be
Im interested if anyone has any other ideas before I check the cats with the 02 sensor trick, and also before I go further and test/take out the injectors for closer inspection.
I have attached a video (link) to show what it sounds like at idle. If you can't hear it I can redo it with my camera rather than my phone, jut let me know.
*listen carefully*
As always, thanks for the info!
Video: https://www.youtube.com/watch?v=_BdT...ature=youtu.be
https://www.youtube.com/watch?v=_BdT...ature=youtu.be
04-18-2016, 04:46 PM
#20
Registered User
So i replaced the PCV valve and MAF sensor and I still have the misfire, NO CODE!!
Im interested if anyone has any other ideas before I check the cats with the 02 sensor trick, and also before I go further and test/take out the injectors for closer inspection.
I have attached a video (link) to show what it sounds like at idle. If you can't hear it I can redo it with my camera rather than my phone, jut let me know.
*listen carefully*
As always, thanks for the info!
Video: https://www.youtube.com/watch?v=_BdT...ature=youtu.be
https://www.youtube.com/watch?v=_BdT...ature=youtu.be
Im interested if anyone has any other ideas before I check the cats with the 02 sensor trick, and also before I go further and test/take out the injectors for closer inspection.
I have attached a video (link) to show what it sounds like at idle. If you can't hear it I can redo it with my camera rather than my phone, jut let me know.
*listen carefully*
As always, thanks for the info!
Video: https://www.youtube.com/watch?v=_BdT...ature=youtu.be
https://www.youtube.com/watch?v=_BdT...ature=youtu.be
I fixed the misfire. My issue was a bad coil pack just like everyone else. I changed all six, but somehow got a "bad" one again in the second batch (different brand).
Great write up on this issue, it helped me out a lot in terms of diagnosis and figuring out how to resolve my issue.