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hi guys i have a r33 gts-t this is my problem, When i em in high rev's any wher between 5 to 7,000 my car starts to jerk and lose power. i know it could be hundreds of things but i want to know what you guys think it could be and if this has happend to any one else. THANKS IF YOU CAN HELP AND GIVE ME SOME FEED BACK

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hi guys i have a r33 gts-t this is my problem, When i em in high rev's any wher between 5 to 7,000 my car starts to jerk and lose power. i know it could be hundreds of things but i want to know what you guys think it could be and if this has happend to any one else. THANKS IF YOU CAN HELP AND GIVE ME SOME FEED BACK

Could be faulty AFM. Swap over if u have access, if not then resolderthe electrical contacts. Also check your coil packs.

Also if you have a pod filter, unsecured, get a CAI box or replace it withyour stock air box as this is what caused your problem with AFM.

99% chance it will be your ignition coils shorting out wich is a VERY common problem on the RB25DET engines

Quick test, take cover off the coils (black cover on cylinder head).. one way You could check them is to start engine and try to look for sparks whils reving and in the dark, But for mine the best way to diagnose if they are faulty (shorting out) is to give them a good spray with Inox (can be brought from bigw/ boating store etc) make sure you coat them well!.. than take the car for a good hard run and ill just about bet that you will no longer have the missing above 4500rpm, however this is not a permament fix.. it might last a few weeks max

The inox is insulating the parts of the coil that were beforehand leaking electricial current (shorting out) causing your engine to miss at the higher boost setting wich comes in at about 4500rpm from memory

If the coils are your probem there are ten thousand pages on here about how you can fix them or you can buy splitfire aftermarket ones wich is what some people do but your looking up to $1000.. i thing Sliding performance has a good deal on them atm for about $5/600

Dave

Edited by r33freely

You can check your coilpacks very easily. Remove the plastic cover over them. Then go for a 'spirited' drive at night when it's dark. Try to recreate the situation where the engine does its bad thing. Then pull over and pop the hood and stick your head in over the packs. I had bad packs, and when I did this, I could clearly see the spark arcing on 3 or 4 out of 6. Bought new packs, and 100% fixed.

Just easy to check this first since it's such a common thing in 'lines.

  • 2 weeks later...
Just to let us know my car is stock all it has is a front mount and a pod filter

I had the same prob last week, it mostly occured when dropping down in gears on the freeway. it was my coil packs i took em out painted them with nail polish , it fixd them for now, i dare say coil packs are most prob next on my shopping list...

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