Missfire After Change Of Plugs....help A New Skyline Owner!

[33driver]

Hey guys,

Well i've owned my R33 GTS-T for just over 6 months now. Very happy with the car so far. I finally got round to changing my plugs today. However it didn't end in a happy ending .

Problem: Finished changing the plugs and went for a run, at first thought sweet, felt like a bit more bottom end tourqe. But as I start to build revs, I'm getting a miss after 4500, around 5000 revs. Feels like spark, not fuel, which is about right considering I only was playing with the ignition system.

What I've done:

The plugs I pulled out were HKS S35i plugs (to my surprise). I replaced them with NGK Iridum BKR5EIX-11 plugs. I was ultra careful checking all the plugs and the coil packs when putting everything back together. I'm wondering if the boots around the coil pack may haven cracked after I cleaned them and man handled them. But i'm not sure. I would assume that would allow a break done in spark if the boots were cracked.

Thoughts? I read the sticky about the miss fire, however do they mean put tape around the boots themselves? Not sure

Edited June 10, 2007 by 33driver

[ceedub]

check plug gaps

what were the old plugs set to?

if that doesn't work get some platinums.

I've found iridiums don't work too well.

[33driver]

i'll have to have a look tomorrow the hks plugs did look a bit closer to the electrode though from memory

[Nathan_G1]

what it sounds like is your blowing out spark coz the factory NGK gap setting is 1.1mm, take them all out, re-gap them carefully to 0.8mm and put them back in, make sure u spray silicone spray on your coilpacks before you put them on the plugs.......this increases seal and conductivity.

this should fix the problem......if it keeps going, make sure you did re-gap them right, or change plugs to a better cold rating like like PFR6G-11, there cold rating is 6 which is the highest for street use..........you wont need any higher

but remember, decrease your plug gap this is key. 0.8mm mate

[salad]

Yeah, smaller gap works better. I just use coppers in my car, BCPR6ES, I've seen a few people with R33s use these aswell with good results. For the $2.50ea or so they're worth, you should have a think about em

[33driver]

we managed to fix the problem today. The original HKS ones that were in there were gapped to 0.6 which we thought was a bit small. Apprantly R33's should be about 1.05mm? The NGK's were at 1.1mm liek you said. We regapped the NGK's to 0.8mm and it worked perfectly. Not sure why the old ones were at 0.6mm, might have been compensating for something else that we will no doubt find out in the future hehe. But we are fixed for the moment.

Cheers,

Matt

Edited June 11, 2007 by 33driver

[Nathan_G1]

depends if the old HKS ones are Non-projected plugs or not.........sometimes they come like that factory for a permanent spark rate. However it seems small.

salad is a lucky person when he can run $2.50 spark plugs.......unfortunately a small rule of thumb is as you gain more power your plugs must suit and be 1-2 cold ratings higher then HP.

[LiQuid IcE]

I run coppers as well gapped to .8mm because my tuner recomended it. But its not the recomended plug by NGK... THe NGK only lists platinums and iridiums for R33's....

[superspit]

we managed to fix the problem today. The original HKS ones that were in there were gapped to 0.6 which we thought was a bit small. Apprantly R33's should be about 1.05mm? The NGK's were at 1.1mm liek you said. We regapped the NGK's to 0.8mm and it worked perfectly. Not sure why the old ones were at 0.6mm, might have been compensating for something else that we will no doubt find out in the future hehe. But we are fixed for the moment.

Cheers,

Matt

Hi,

it's not fixed for the moment...it is fixed for good!!!

1.1 mm is fine for standard boost R33's!!!!!

Now, I'm guessing that your car has more boost than stock?.....Just remember, as said prior, to keep your gaps at +/- .8mm to compensate for the extra boost and you'll stay fine on future plug servicing!!!!.....note:Do not attempt to clean your Iridium plugs as you would a copper plug.

Also..your current Iridiums are a fine plug..and are superior to copper plugs in many ways......

I use these and my car loves it....Dyno testing has proved that to me!!

Well done on getting your car right!!

Redards,

Spit.

[superspit]

I run coppers as well gapped to .8mm because my tuner recomended it. But its not the recomended plug by NGK... THe NGK only lists platinums and iridiums for R33's....

quote..NGK only lists platinums and iridiums for R33's....

um....as they bloody well should be!!!

Spit.

Edited June 11, 2007 by superspit

[33driver]

actually the car is totally stock! Since i've owned it anyway, I'm the first owner since being in australia. I suspect it may have been running more boost while still in japan. Plenty of evidence to suggest that, but everything appears to be stock on visual inspection. Timing has been played with though as there are marks on the crank angle etc..

Only things 'modded' on it is a crappy catback and turbo timer. More boost is on the way but not yet hehe.

Hi,

it's not fixed for the moment...it is fixed for good!!!

1.1 mm is fine for standard boost R33's!!!!!

Now, I'm guessing that your car has more boost than stock?.....Just remember, as said prior, to keep your gaps at +/- .8mm to compensate for the extra boost and you'll stay fine on future plug servicing!!!!.....note:Do not attempt to clean your Iridium plugs as you would a copper plug.

Also..your current Iridiums are a fine plug..and are superior to copper plugs in many ways......

I use these and my car loves it....Dyno testing has proved that to me!!

Well done on getting your car right!!

Redards,

Spit.

Edited June 12, 2007 by 33driver

[superspit]

actually the car is totally stock! Since i've owned it anyway, I'm the first owner since being in australia. I suspect it may have been running more boost while still in japan. Plenty of evidence to suggest that, but everything appears to be stock on visual inspection. Timing has been played with though as there are marks on the crank angle etc..

Only things 'modded' on it is a crappy catback and turbo timer. More boost is on the way but not yet hehe.

Hi 33,

are you positive that your car is only running 5/7 PSI?....I am willing to bet that it's actually more, due to the symptoms and the 'fix' you made going forward, (spark gaps), whether it's due to a leak in the W/Gate line or just modded that way (?).

I'm not sure if timing can give the same effect as the wrong spark gap under higher boost....maybe it can(??)

Anyways, I too was the first owner of my line here in Oz, and found that an increase in boost of just 3psi had the exact same results as yours did prior....

regards,

Spit.

[33driver]

Thats interesting you mention the wastegate. Everything appears to be stock on the outside, when we purchased the car I had a few people look at it and they thought it felt slightly underpowered. Never driven a R33 before I didn't really know wat to expect. After treating it to some good fuel and going over it I've been quite happy with the power. However recently I have been getting a whining sound form the turbo at high revs. When I say whining sounds, we have locked it down to a fluttering wastegate sticking or a slightly blown exhuast gasket or a combination of both. That sort of whining. Might be just a combination of sticking wastegate or something? Might be where the two are linked and just a fluke hehe.

Where would I look to see if it was modded for more boost? I would assume the wastgate would be altered which might be a bit hard to tell?

No idea about timing and spark gap being linked, first turbo car so not sure to be honest. I know timing altered the way the engine ran in my last car at different RPMS with misses etc...

Hi 33,

are you positive that your car is only running 5/7 PSI?....I am willing to bet that it's actually more, due to the symptoms and the 'fix' you made going forward, (spark gaps), whether it's due to a leak in the W/Gate line or just modded that way (?).

I'm not sure if timing can give the same effect as the wrong spark gap under higher boost....maybe it can(??)

Anyways, I too was the first owner of my line here in Oz, and found that an increase in boost of just 3psi had the exact same results as yours did prior....

regards,

Spit.

[33driver]

hey,

Was driving to work this morning and the missfires started to creep back. Didn't do it all the time and it was after the car was warmed up and at 5000+ revs mainly in 3rd gear, was fine in 1st/2nd didn't rev it hard past 3rd hehe. Very cold morning so I'm thinking that the gap needs to be closed maybe another 0.1mm. Was also getting a hesitant miss every now and then at idle but that was there before I changed plugs (although it is slightly more pronounced now) so i'm ignoring that for the moment.

am I on the right path? I suspect there is something else going on though. The coil packs look in A+ condition, as sighted by me and my mechanic. But i think i'm going to invest in some splitfire coil packs to make sure the spark getting there isn't a problem.

matt

[superspit]

hey,

Was driving to work this morning and the missfires started to creep back. Didn't do it all the time and it was after the car was warmed up and at 5000+ revs mainly in 3rd gear, was fine in 1st/2nd didn't rev it hard past 3rd hehe. Very cold morning so I'm thinking that the gap needs to be closed maybe another 0.1mm. Was also getting a hesitant miss every now and then at idle but that was there before I changed plugs (although it is slightly more pronounced now) so i'm ignoring that for the moment.

am I on the right path? I suspect there is something else going on though. The coil packs look in A+ condition, as sighted by me and my mechanic. But i think i'm going to invest in some splitfire coil packs to make sure the spark getting there isn't a problem.

matt

mmmmm......do check your IC piping too.....anything that even looks like a leak (black residue around piping) should be a good indicator that it is.

Also, what is your boost guage showing at full boost? (prior to 'missing?)......please don't hurt yourself trying to find out though!!!

[d00dz]

Replace the coils.

or do the ghetto mod and tape em up and see what happens..

But for $510 for coils it's not a bad investment.

[33driver]

yeah coils are on the 'next to buy list' though i have to say the ones i have look pretty damn good. $510? they splitfires and where from? cheapest i saw was slider performance which was $525 delivered

I"ll check the piping i played with when i get home, some of the houses were a bit old, might have ruptured one.

Ah I love cars.

On the plus side I just got the car back from having it tinted hehe.

[d00dz]

Yea oops yea $525 from slidez0r

[33driver]

hey guys,

just a further update to my problem. Starting to sound like a combination of coil packs and the gap being a bit to big still (for watever reason).

I get missfire at EXACTLY 3.5 on the stock boost guage (so i'm reading that as 0.35 bar) in first and 2nd gear, as the load lessens I guess, i don't get a misfire in 3rd gear +

The car is idling like crap and missfiring all over the place as well. Seems to be heat related because when the car is cold, its fine (expect for the missfire on boost). If i drive the car, let it get hot. Park then come back a while later the problem is worse. Because of the heat relation i'm suspecting coil packs. I'm just curious as to why its doing it now, straight after I changed the plugs. Note that inbetween idle and full boost, the car is perfect and runs great at cruise rates.

Tell me oh gurus what your thoughts are lol. :sorcerer:

[Luciano]

when i was driving my 33 around with un-gapped NGK iridiums, it would accelerate happily to 5000rpm, but then flat spots/misses all the way up to redline. it would only do this in cold weather, no matter what the engine temperature level. On a hot day (say 30+ degrees), it would not miss at all... (im guessing due to the lower boost levels [i dont have a boost controller or bleed valve]).

as superspit says, Maybe it is a vaccum leakage of some sort 33driver...