Problems With R33

[psi-gtst]

Just got my first skyline(r33 gtst s2) the other month and was impressed with the performance and overall car, i got it 100% stock so i put in a KN pannel filter next i got some yellow jacket coils and new spark plugs( NGK iridiumi BKR6EIX-11) car was running fine then i fit the plugs and coils and car was running rough as and would misfire after 4000RPM so i thought it might be the coils i put the old ones back in and it was fine at idel but still missfires at 4000rpm.

Can someone help a newbie out?

Thanks

[Ty1]

air flow meter might be the culprit

[blind_elk]

If the air flow meter is faulty, engine is limited to 2500rpm.

I think you will find that in a stock engine, the plugs should be BKR5EIX-11.

[psi-gtst]

iv ordered a new AFM and hopefully that fixes it anyone know why it would start playing up after the new coils though?

[Miguelone]

You were just told about plugs which you changed at same time as coils, you were also told it's not likely to be afm. Why ask questions if you're not going to listen to advice given?

[SiNNO]

100% sure all the coil looms are plugged in correctly? I had this problem on mine, turned out one wasn't fully plugged in.

If not, try changing plugs as blind_elk mentioned.

[GTR-N1]

And check the gap on the plugs.

[StevenCJR31]

what is the condition of your coil pack wiring? dried out and crispy?

[vh45tt]

Sounds like plug gap. Gap the plugs down to about 0.8mm and the misfire should dissapear. Iridium plugs are not the best for forced induction. They have a really small contact point and a large plug gap the spark phsyically blows away from the electrode under revs and boost. So gap them down or go back to 0.9 on a standard ngk. Ive used standard ngk in cars making over 800hp.

Regards

Drews performance

[psi-gtst]

put in the new plugs ngk bkr5eix-11 in and still nothing has changed???

[Miguelone]

Did you try gapping them down to .8?

[psi-gtst]

yeah used feeler gauge they are at .8

[psi-gtst]

any ideas?

[Direstraights26]

Looks Like everyone ditched ya lol

Diagnosing problems can be a pain in the arse but half the time its process of elimination.

And thats the easy part.

ask yourself these questions.

did you get it past 4000rpm when you first drove it or before you installed the plugs and coils?

the problem could of been there before you brought it.

If thats not the case then something you put on the car is giving you trouble,its to coincedental.

Get a mate rev it to 4grand and do the ol' disconect a coil at a time test to see which cylinder is playing up

that will give you a leg to stand on.

you have set the gap and 100% sure you have the right spark plugs?

then its not them,you didnt say if the coils are brand new if they arnt test the resistance with a DMM

also maybe ur air filter is in the wrong way haha.

if the prob is fixed let me know what it was

[gts-4 dreamer]

And check the gap on the plugs.