R34Gtt Missing From Mid To High Rpms

[JustinP]

Geeeez it's obviously the coil packs. Just bite the bullet, buy some Splitfires, and enjoy some trouble free motoring for a few more years (or at least until something else breaks!)

[rondofj]

Cheers guys guess its looking more like coilpacks

[Legionnaire]

Yep, I think you should just replace them. Even if you current issues aren't caused by coilpacks, they will eventually die, every RB25 Neo suffers this problem sooner or later, so you won't be wasting your money anyway, you'll just be acting proactively.

[rondofj]

Gud idea, at how many kms did yours start failing??

[Legionnaire]

Mine broke down at 60-65 kkm, some may live up to 100 000. Started misfiring under boost, then at lighter loads, then sometimes even refused to fire at idle and obviously missed at cold starts (read bore wash). I changed plugs, that didn't help. Checked coilpack wiring - all good. I picked a set of used coils from my previous engine, used to have 25DE before engine swap, and replaced failing coil. That hepled until next coil started to fail - in less than 1000 km after the first one. Since then I replaced three more coils, and although everything's working fine now, I'm thinking about allocating some money to replace all coils with new ones, just haven't decided what to choose yet - splitfires or a set of new OEMs.

[V28VX37]

So what could be the issue?? Coilpacks?? I only just taped them- miss was there before- do the couls inside get stuffed??

Coil packs are a likely cause but not necessarily the only one. In my case we chased a similar issue for ages and it turned out to be a busted crank angle sensor (CAS) - ok at low revs but misfire & loss of power at top end. Have a read of this, it's got a bit of a checklist on what to look for:

Resolved Misfire In R34 Gtt - Rb25det Neo

It can certainly be sorted but can be a PITA as there are so many possible causes. Good luck.

[Josh...]

Rondo Ill sell you my oems ;-) nothin wrong with them just changed to splits I take big tune coming up ??

[rondofj]

Nah thanks Josh, Im selling my OEMs now lol, just ordered the YJs as they have a 2yr warranty and Oz based as opposed to splits bein Jap based and only 6 month warranty plus lot more expensive.. All products have hit n miss bad items btw and both the YJs and Splitfires have numerous happy customers and few dud items too..food for thought.

[rondofj]

Btw i am at 93000kms so about time too, dont think i have CAS issues as my dyno graph is typical smooth exponential not jagged as with a dud CAS..

[rondofj]

Got my YJ coils delivered at work today, geez it was only Sunday when I paid Paul from Performance Wise, he is such a top bloke to deal with!

Cant wait to put them on, will post back with results, hopefully it will solve my miss-fire and farting.

[Rolls]

Same as my reply in the other 3409873 thread with this IDENTICAL problem.

Combination of bad spark from bad plugs or bad coils, or more boost meaning a 0.8mm gap is needed or too much boost on stock ecu/tune causing engine to run extra rich (9-10:1) which needs an even stronger spark than stock to avoid getting blown out.

So fix your plugs first, then your coils, then get a remap so you aren't running super dooper rich. One or most of these things will be needed to fix your problem.

[rondofj]

I mentioned earlier that im running 0.8 gapped coppers and a tuned Nistune ecu so it has to be coils.. Fingers crossed..

[Simon-S14]

r34 coils are terribly unreliable. ive had to replace dozens of sets

[rondofj]

So I just had a blast in my 34 after putting in my YJ coil packs yesterday- just SO happy with the difference it made! My previous miss-fire, farting n power loss has gone completely and car just PULLS so hard n clean all the way to redline, just so crisp n beautiful to drive, fat power n torque everywhere, no missing at all and gained a chunky midrange n total response, yes even a 'only 200rwkw' GTT is keeping us grinning for ages like pubescant teens..chirped tires a few times too while driving n turning gradually.. So if you need coil packs, just GO FOR IT, it makes a huge difference if your originals r shagged..

[Rolls]

Glad to hear it was just the coils mate!

[DVS JEZ]

Now time for a bigger turbo Ron

[rondofj]

Ur right JEZ, just tossing up between the SS1PU and TD06SL2-20G 10cm housing, do u have good things to say about the Kando, hope u've tuned it past ur initial 9psi and now sliding all the way up your driveway! I'm just deciding if its possible to cut my bellmouth jjr dump n weld a v band adaptor in there as its a circle trying to mate with a bellmouth oval..

[DVS JEZ]

Of course u can. U cut it off down near the ac outlet but. Plenty of room for a 90 degree bend then.

Ill take u for a run in the drifter next time u come up.

[Legionnaire]

Here is an idea - buy a GTX2867 and put it into factory rear housing.

Should be nearly bolt-on installation, possibe to be done with internal wastegate, stealthy, no need to change dump pupe and will easily give you nice and snappy 260-280kw

I have done some calcs. This turbo is going to be great on nearly factory RB25. Tune it up to whatever limit you'll hit first, be it injectors or AFM, and replace limiting parts later.

Edited December 19, 2011 by Legionnaire