Help. Random Missfire Between 1000 And 3000

[Zuydam]

Ok i needed to get a RWC the other day. before this my car randomly cold in the morning in second gear when driving out of first obviously it would skip. or missfire randomly feel jumpy. ok and the other day i washed and degreased my engine bay got some water under the coil packs cover. started the car up and it was missfireing. so i took everything off and blew out the coilpack area for like 20 minutes making sure everything was dry. it stopped the missfires. but then the next day. all the time no matter what driving through 1st 2nd and 3rd i get random skips feels like its missfiring between 1000 to 3000 after 3000 it clears right up and is smooth as but accelerating from 1000 -3000 is skippy and missfiring.

anyoen think its my spark plugs?? or coil packs??
ive also seen maybe O2 sensor but how do i check that. i know its in the Cat but how do you test it if its ok. or should i just go to like auto tune and get someone to plug in to my car.

[MatthewT85]

i dont know how to test it, would be good to know if you can, they are cheap though....

but also if your car's a 33 the o2 sensor is in the dump pipe, the one youre talking about is the sensor to tell you if the cat is screwed...

sorry i cant be more help...

[niZmO_Man]

Tried cleaning the AFM?

Sensor in the cat is the temp probe so ignore that. As stated, the O2 sensor is on the dump pipe.

Also a good idea to change spark plugs if you haven't done so recently. BCPR6ES-8 is what you want. Don't bother spending more on the expensive ones.

Have you looked at changing the coil packs if they haven't been changed recently?

[Pr0x1mity]

Skyline coilpacks are a SHHHHHHHHHHH of a thing. Change them out for yellow jackets if you are poor, spitfires if you have the $$. If its factory coils then you got a good run out of them on an R33. R34 ones usually only last 100,000km tops before one starts to go poo.

[Zuydam]

yea my 33 has done 211k but ive heard a coilpack when gone missfires at higher RPm not low ones.

this weekend ill replace my spark plugs and clean my AFM see if that helps. thanks everyone.

if the O2 sensor is gone. wouldnt a check engine light come on though thats why i dont think my O2 is screwd think it should be fine.

[niZmO_Man]

Nah, you'll have to take the O2 sensor and and shake it. If it's rattles, replace.

But if they're 50,000+ km old then replace them anyway.

[Josh080691]

Check ur plugs. If there fine let it idle for an hr to dry out. Keep the hood open and in the sun

[vspecIInur]

Happened to me 2 weeks ago on my evo. One of the spark plugs was absolutely fried. Replaced them all and back to normal

[Zuydam]

Found out in my midnight rush to dry out the coil pack area i practically snapped 2 very old brittle vacuume lines. popped the bonnet yesterday went to start pulling everything off to do spark plugs. got 2 vacuum lines of looked at them and 2 big splits on either end of each hose replaced them both with ordinary air line from my work(diesel mechanic) replaced my spark plugs whiulst i was at it. they wernt to bad but thaught might aswell least i know there done and when was done.

no missfires since still needs turbo though hahaha

[vspecIInur]

Glad to hear you sorted her out mate