Misfire But With A Difference

[mr_crust]

my r33 has always run perfect, but a few months back i changed a coil pack as it was buggered (the car idled like it had a v8 in it) so after putting in new coil packs and changing the spark plugs things were fine.

no i have a slight hicup at around 4800-5500 but the thing is its not always. 99% of the times it drives without an issue, but late at night when its cool weather it feels like it pops between that range and then recovers real quick.

mods are:

FMIC

10PSI

HIFLOW cat

3"exhuast.

any ideas, my guess is the stock fuel pump

[SXR]

my r33 has always run perfect, but a few months back i changed a coil pack as it was buggered (the car idled like it had a v8 in it) so after putting in new coil packs and changing the spark plugs things were fine.

no i have a slight hicup at around 4800-5500 but the thing is its not always. 99% of the times it drives without an issue, but late at night when its cool weather it feels like it pops between that range and then recovers real quick.

mods are:

FMIC

10PSI

HIFLOW cat

3"exhuast.

any ideas, my guess is the stock fuel pump

did you gap the plugs?

[The Mafia]

could be the plugs not gapped, OR pinging.

If its pinging, FIX IT IMMEDIATELY....

Colder nights means more air....then she'll ping and blow away your ring lands..

[mr_crust]

plugs are gapped down to .8mm . im pretty sure its not pinging

[BAMR33]

Yep, I think you're right about the pump or perhaps even just the fuel filter. How many k's does your car have on it?

[BAMR33]

Wouldn't be the plugs or it would be worse during the day due to the heat factor.

[mr_crust]

ive just clocked 67,000ks on it , the fuel filter would be 18,000ks old, how often do i replace that?

[GTshortie]

a few questions:

1. Did you replace your original coil packs with brand new spitfires/oem ones? Or did you get some used coil packs?

2. My car had similar problem, on a cold night my car usuallys boosts a little bit higher then throughout the day and had a small hiccup like you descriced around 4000-5500rpm mark.

Tried regapping my copper heat range 7 plugs from 0.8mm to 0.65mm it was good for a quick fix like others have said on the forum BUT it just hides the truth that the coil packs were on there way out. Car didn't feel as quick as it use to compared with when i ran a higher gap keep in mind.

SOLUTION:

Recently i've ordered a BRAND NEW set of Spitfire coil packs from www.perfectrun.com.au for $550ish delivered.

Didn't change my plugs or gapping (NGK Copper Heat Range 7 plugs 0.8mm standard) the plugs in the car's done around 1000kms.

Just fitted my SPITFIRES coils and what do you know! boost at 1.0bar (low), boost at 1.3bar (high) and NOT one sign of misfire SMOOTH reving all the way to redline LIKE IT SHOULD BE!..

my 2 cents.

[mr_crust]

thanks mate, i replaced the damaged coil packs with factory ones from another r33 and it fixed all the idel problems i was having, but no i have this small thing happening....if the coil packs are gone again im gonna be pissed

[Kennedy]

Get on a Dyno to see if it's your pump. If it's not it most likely spark arcing from cracks in your coils....or even a crack in your cooler piping

[mr_crust]

after takin it for a few test runs, my guess is its not coil related, as if i press the accelerator 80% it doesn misfire at all or pop, it only happens when i have the foot to the floor when it misfires, so its the fuel pump which needs an upgrade or the air/fuel ratio

[--{TRYDIS}--]

if its only missing at night then you should be right mate all it is, is the cold night air is more condensed therefore partially upping your boost to certain point were your sparks need a smaller gap or you might be hitting boost cut... if shes working perfect during the day then dont worry bout it too much. if its bothering you try getting a boost cut defender and see if that makes a difference. cheers mowie

Edit: just reading over the post again try getting ur A/F Ratio remapped like everyone is sayin if all else fails.

Edited October 26, 2006 by --{TRYDIS}--

[mr_crust]

cheers for the advice buddy