Nm35 Intermittent Missfire

[DrLui]

I'm having a slight intermittent misfire, not sure if you can hear it in the video bellow but it normally happens around 2500rpm when driving, at 21 seconds into the video you can hear the miss around 3000rpm.

It only happens when the car is warm, when its cold it drives perfectly fine also after the car is warm it sometimes misses at idle as well.

I have replaced the spark plugs, checked the coils and replaced the O2 sensor. I am not getting any error codes, and this was present before i did any mods to the motor (i.e electronic boost controller and BOV)

Any help would be greatful

[joshm35]

Afm?

[DrLui]

Afm?

I did think that, I quickly swapped it over with my spare one at lunch and still no go

[joshm35]

Take out the coil packs and see if one has a hole in the stalk and if its arcing out.

Also could be a fuel issue. Check to see if the vacuum lines to the fuel pressure reg.

[DrLui]

I've checked for air leaks, and pulled the coils out to check them prior. I reckon it wont hurt to check them again, but if its the coils it doesn't explain why it works perfectly fine when its cold.

[admS15]

I've checked for air leaks, and pulled the coils out to check them prior. I reckon it wont hurt to check them again, but if its the coils it doesn't explain why it works perfectly fine when its cold.

Dodgy coils tend to play up when they get hot. Not saying that is your problem though. Good luck and let us know what it ends up being.

[YangLIU]

warm missing problem may related to sparks/coils

[DrLui]

Hopefully its just that. I have a couple of spare coil packs, ill try and suss it out

[scotty nm35]

What do the plugs look like? Take a pic if you can. That should tell the story.

[DrLui]

After work today I decided to test further into the coils, as I have tested the resistance across them and everything seemed normal.

Got the car warm after work (which is hard because I live 2 mins from work) and got it missing.

Went through each individual coil pack unplugging it while the engine was running and listening for the miss.

Got to the middle passenger side one and when I unplugged I didn't get the intermittant miss.

Keeped checking the rest of the coils and every time I unplugged the could I would get the miss.

So I swapped that coil and now it's running smooth.

The pic shows slight damage to the old coil

It's amazing how much that temporary miss would effect the feel of the car, but it's a much nicer car to drive now.

Thanks everyone for their help

[joshm35]

Ahh good. Great news mate.

[YangLIU]

After work today I decided to test further into the coils, as I have tested the resistance across them and everything seemed normal.

Got the car warm after work (which is hard because I live 2 mins from work) and got it missing.

Went through each individual coil pack unplugging it while the engine was running and listening for the miss.

Got to the middle passenger side one and when I unplugged I didn't get the intermittant miss.

Keeped checking the rest of the coils and every time I unplugged the could I would get the miss.

So I swapped that coil and now it's running smooth.

The pic shows slight damage to the old coil

It's amazing how much that temporary miss would effect the feel of the car, but it's a much nicer car to drive now.

Thanks everyone for their help

i have splitfire and NGK range 7 on my hand right now and will fit them when JEZ retune my car this weekend. i think the imtermittent missing problem is common issue for M35. mine also has imtermittent missing when warm idle and mid range revving

note: when warm idle in D with brake pad pressed, rev should be 550rpm. my car will drop to 400rpm imtermittently then back to 550 in one or two seconds.

Edited May 17, 2016 by YangLIU

[joshm35]

I hear stock coil packs goes for 2000

[scotty nm35]

Never had mine intermittently missfiring, sounds like a tuning issue to me. If the afr's are rich it can blow the spark out and foul the plugs.

[YangLIU]

Never had mine intermittently missfiring, sounds like a tuning issue to me. If the afr's are rich it can blow the spark out and foul the plugs.

someone tuned up boost could kill the stock range 6 sparks/coil in short time, like me

[OZZYR32]

Hi there gentlemen, I have had this very same issue with my m35 just start this past couple of days. I had taken it into my local nissan dealership to have it checked for any codes (this was before finding how to get the ecu into its diagnostic mode which incidentally didn't work for me today no matter how many times I tried).

It didn't come up with any fault codes but the nissan mechanic seemed to think it may be the CAS on its way out. I have changed the fuel filter today and am doing the plugs and will check the coils as well as cleaning the throttle body tomorrow and see how that goes.

Has anyone else found this issue to be caused by the CAS? I have read most of the posts on this site relating to the M35 and did come across the "CAS issue" that ended up having a recall and have checked to see if mine had been cleared. It does have the sticker next to the build plate with the R184 or whatever the number was stamped on it so I'm assuming that had been cleared up.

I'm also wondering if it could have anything to do with the PCV value being blocked? To much pressure built up without being able to be released once hot?

Sorry about the monster post. I'm just thinking of anything it could possibly be as I am meant to be driving to vic this weekend to watch the drifting.

Cheers guys.

[admS15]

Try the filter and plugs and inspect coil packs before doing anything else. Hopefully that sorts it. I'd be careful about cleaning the throttle body. If you move the throttle plate at all you will need to do the idle re learn procedure.

As far as the diagnostic mode goes, you have to get the timing sequence spot on for it to work. It helps if you use a stopwatch. Good luck and hope u get it sorted.

[OZZYR32]

Thanks asmS15. I did also try the throttle position relearn and idle relearn today aswell as I disconnected the battery and computer 2 weeks ago whilst doing the brake cut mod. But they didn't seem to make any difference either.

[OZZYR32]

Ok I have found a massive issue. So far 2 out of 4 plugs I have changed have had oil in the spark plug hole.. but this one is literally drowning in oil. I'm taking a guess that the rocker cover gaskets have shat themselves and require changing.

I'd like to just ask if there could be any other issues this could be from?

[YangLIU]

maybe you would like to read this, also oil in plug hole

http://www.sau.com.au/forums/topic/423006-my-engine-has-issue-but-cant-quite-put-finger-on-it/page-2?hl=%20compression%20%20test