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UPDATE:

the issue of breaking down at 5psi is gone after fixing a small leak it had in the int. piping. but there is still a massive power loss, along with the stalling issue as well as the minor missing under load.

ok, so the story starts at a drift practice where at the end of the night i noticed a few issues happening. the first was it started stalling after coming down from over around 3000rpm, the idle control would just not catch it and it would fall down at struggle around 100rpm until dying. now at first i thought owell just some idle control issues, probably related to heat from being thrashed etc. then i noticed some breaking down at higher revs and some hesitation when i backed off the throttle, not to mention a decent lack in power. now once again i put this down to heat issues at the time, probably a coil pack breaking down or something.

anyway, the next day comes and i start off with a nice cold engine, but i start noticing the issues happening again and still with a lack in power (it was spinning first up easily only a day before, now nothing. along with a general feeling of gutlessness). anyway i took it into a reputable workshop boostworx where he had a look and couldnt hear anything serious, there was a busted alternator bearing making a bit of a noise but thats about it. he recommended cleaning out the idle control solonoid and giving the AFM a spray etc which ive already done in the past to try and fix another issue i had. this issue went on for about a week and i decided it might have been plugs so i gave them a change a few hours ago, they didnt seem in all to bad nick and they were decent plugs. so there went that idea. but i thought id take it out for a drive and see if it make any improvements. so i went up a nearby road and gave it a bit of a thrash only to hear the same issue, at first it started breaking down at almost dead on 5psi in both 2nd and 3rd. then by the time i got down the hill it was missing continually and sounded really off.

now for a while ive had a pretty loud tappets noise come on and off. this probably isnt related but its worth noting, im using 10w40 turbolight oil so the oil isnt thin enough to really warrant this.

now, i guess the typical missing issues can be related to something in the ignition, but plugs are fine, coilpacks and igniter seem fine, but it doesnt really sound like them by the way things have happened.

so i guess im just after some ideas, the main thing that has got me worried is it all seems to happen after being thrashed and given a beating, it doesnt seem to be a linear deterioration or something that happens with heat etc.

but yeh throw me some ideas, cheers.

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i had that a few months ago, got my timing re-adjusted that fixed it dying when coming to a stop, and i was loosing power up top so i got splitfires and stop the top end hesitation. but that was just my experience, your problems could be something diffrent?

Good luck

AiF

JustJap have a coil pack replacement thats $399 vs the $500 odd for splitfires.

They 'look' like a set of coils I've seen that had F.E.T branding. Might be worth a look. :thumbsup:

Have you tried siliconing up your coils? Worked for me. Mine were popping at std boost with std turbo; siliconed them up and now I'm at 15psi and making 268rwkw without a hint of missfire.

I suspect when I ramp the boost up they are starting to cause a few problems so I'm stil up for a set of coils. :whistling:

Not sure if I should try the JJR coils... I keep thinking to myself poor/tight man pays twice which is very much true when it comes to modifying cars.

JustJap have a coil pack replacement thats $399 vs the $500 odd for splitfires.

They 'look' like a set of coils I've seen that had F.E.T branding. Might be worth a look. :D

Have you tried siliconing up your coils? Worked for me. Mine were popping at std boost with std turbo; siliconed them up and now I'm at 15psi and making 268rwkw without a hint of missfire.

I suspect when I ramp the boost up they are starting to cause a few problems so I'm stil up for a set of coils. :)

Not sure if I should try the JJR coils... I keep thinking to myself poor/tight man pays twice which is very much true when it comes to modifying cars.

what do u mean by siliconed them? i think ive heard of this before but not exactly sure what it means. ive got a few spare stock coil packs i can chuck in. i think im going to isolate the cylinder then try changing the coilpack. if nothing happens im going to drop into boostworx again while its still misfiring and give him another listen.

and the car has just been tuned to timing was only adjusted not long ago.

eh, couldnt get it to miss all the time, just when accelerating a bit of dodgeyness and at 5psi massive breakdown, so couldnt isolate the cylinder right now. might just try swapping some coilpacks over and see what it does.

Grab some silicon and cover the base of the coil pack while trying to push some in between the bracket and the coil pack its self.

I found the best way to find which coil was arcing out was to remove the centre coil cover wait for night; take the car for a drive get it warm, park, leave the car running and then watch the lightening show. :D

If you can't see anything give it quick blips of the throttle and watch down the sides of the coils.

All 6 of mine were arcing out. >_<

Same as cubes. Lightning show around 4 out of 6 coils.

Stripped them out, layed on a few coats of electrical varnish and then high temp silicon around the frame parts where it meets up with the coil itself. Seems to have done the trick for now. Looking at the jjr coils as a replacement though..

james.

I replaced all my coil packs when I had a simular issue on the old r32. Turned out engine heat was causing the ignitor to misfire the coils. The ignitor was actually fine, as was the coil packs. The clutch in the thermo fan was stuffed though and that was causing the engine to run about 10-15 degrees hotter than it should, over boil occasionally when shut down, and also have a miss-fire issue very simular to yours.

Make sure your plug gaps are at 0.7mm too. Too large a gap will cause hesitation and missing as boost pressure/cylinder pressure rises.

if its any help I think i've got the old coil packs around here somewhere if you want them? $20... for the lot if i can find them :(. Make it worth my while do go digging in my garage...

i just checked mine at night, 5 of em are arching, but it only misses on idle every now and then, i'm running std boost etc, would this arching maybe be losing power from it? also do r32 gtr coils fit to rb20det?

Chris...

Yes RB20 and RB26 coils are the same.

If its arcing outside the coil its definatly not arcing across the electrode. Also once its arced through the insulation once it leaves a carbon track through the insulation, so it will continue to arc through that area the insulation has broken down. Its not repairable, only replacing the coils will solve that problem.

Cheers,

Ian

Yep the sad sad truth.. :(

However, silicon has definitely bought myself and others a little time. The silicon trick is most likely fine for the stock turbo setup but with any more boost than 1bar I'm having issues with weak spark.

Initially its noticeable as you can see unburnt fuel hosing out of the exhaust on the dyno; keep pushing boost in it gets worse and power goes to shit/spikey/lumpy.

JJR coils; I need to see some solid proof they are good for high combustion pressures.

If I go and push in 1.5-1.6bar and it starts breaking down even with a small plug gap I'd be depressed I had just wasted $400 in coils when I could have spent another $100 and bought the proven splitfires. So JJR sponsor me. hahaha :(

I replaced all my coil packs when I had a simular issue on the old r32. Turned out engine heat was causing the ignitor to misfire the coils. The ignitor was actually fine, as was the coil packs. The clutch in the thermo fan was stuffed though and that was causing the engine to run about 10-15 degrees hotter than it should, over boil occasionally when shut down, and also have a miss-fire issue very simular to yours.

Make sure your plug gaps are at 0.7mm too. Too large a gap will cause hesitation and missing as boost pressure/cylinder pressure rises.

if its any help I think i've got the old coil packs around here somewhere if you want them? $20... for the lot if i can find them :(. Make it worth my while do go digging in my garage...

yeh this definitely isnt a heat issue, ive had a heat issue before. might be interested in the coilpacks tho, sought through them and find ones that dont have issues. chuck me a PM when u find them and ill probably take them off ur hands. are u in SA? if not would u be willing to post them?

pity i got on the piss tonight and couldnt end up driving it up and checking it, ill do it tomoz.

just took it up then, had a look and couldnt see any sparking :S

hasnt got any worse, still seems to break down at 5psi. and it feels like more than one cylinder, not like a loss in power but an actual break down and it just chokes and cant go further, if u keep ur foot down it starts jolting violently.

could it be injectors maybe? or still rekon its coilpacks?

you need to do the list...

1. Compression test.

2. Test each coil pack.... use an old plug and start the car running on 5 coil packs with the 6th hanging free with an old plug in it. Disconnect the associated injector plug for that coil pack when your doing this. Earth each plug on the engine where there is clean metal (not paint). AS the car idles look for an even spark.

3. Are the plugs new? BCPR6ES at 0.7mm plug gaps

4. Clean maf sensor using CO spray

5. If all else fails, pull the injectors and get them cleaned. Replace the fuel filter too.

Good luck.

Edited by Vspec R33

And I forgot one other thing... Loose hose clamps. You might have a hose clamp loose, so its sucking a heap of air through the turbo and blowing it all out an air leak, and at the same time overfueling the hell out of the engine. Every hose clamp from the throttle body, thru the intercooler to the turbo compressor housing must be checked.

I'd be putting this at the top of the list to do before the compression test.

Cheers

Ian

you need to do the list...

1. Compression test.

2. Test each coil pack.... use an old plug and start the car running on 5 coil packs with the 6th hanging free with an old plug in it. Disconnect the associated injector plug for that coil pack when your doing this. Earth each plug on the engine where there is clean metal (not paint). AS the car idles look for an even spark.

3. Are the plugs new? BCPR6ES at 0.7mm plug gaps

4. Clean maf sensor using CO spray

5. If all else fails, pull the injectors and get them cleaned. Replace the fuel filter too.

Good luck.

1: yep, its just i dont have access to a tester and i dont have much $$ to throw around for stuff that doesnt need to be done, so id prefer to rule out other things first

2: only problem there is they are definately all sparking on idle, how well not sure but there is no obvious miss there so testing this would be hard. they only start to break down under load, only thing i can think about is chucking it on a dyno and checking it then.

3: just replaced the plugs, ones that came out were ok and were BCPR6EY gapped at 0.8, same as the ones i just put in.

4: u mean AFM im assuming, yeh i was gonna give that a clean for the idle issue, but i didnt really think it was the source of this breaking down issue.

5: like the comp test i wanna make sure its not other stuff before i fork out the $$.

Sounds very similar to my RB20 which is currently sitting on an island in the middle of an intersection waiting to cool down :(

Small pop on idle, nothing consistant to tell what cyclinder its coming from. Missfires like a hoe at 4000-5000, it boost all the way to 14psi but hits 4000 and craps out. From idle to 2000rpm is missfires and hesitates, 2000-3500rpm it runs normal.

Sofar I've replaced the O2 sensor, fuel pump, injectors, spark plugs. O2 sensor was replaced with a wideband, before it died tonight I was logging the AFR's and it was all normal, it was trimming to 14.7 on cruise and idle, 12 on boost (tuned stock ecu, nothing touched other than WOT AFR's). Changing the injectors made it run better but not well, also stopped it running very rich (>9 AFR). I also had a loose alternator belt which made the car a bitch to start from it slipping.

ECU & AFM are definately doing there job, both read in the normal (checked via consult) and the fact that the mixtures are correct suggests it not there fault either. With the better part of the fuel system replaced it leaves ignition now. Still using standard coil packs and ignitor, the ignitor I can test using my oscilloscope (will do when I get the f$%king thing home) but since its the last thing left besides swapping the entire engine out I may aswell shell out for a wasted spark setup to rule it out completely. I've got a megasquirt-II waiting to be wired in so it'll make that install a little easier when I wire in the ignition.

I had a mechanic look at it but he just gave it back to me broken and said 'get it tuned on a dyno' :)

Best of luck fixing your problems, I'll post up how I go with the new spark system

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