1jz fine till i hit 13 lbs of boost. little help pls.
#16
Sounds like an ignition problem...try decreasing the gap on the plugs first and see if that helps...If not, you could be having a faulty coil.
When you first mentioned your issue, first thing that came to mind was fuel cut. But apparently you know the difference between that and a ignition problem.
Another thing you should be checking for is boost leaks. Its real easy to do, just need a compressor and a couple of plumming parts u can pick up from home depot.
PM me for details if your interested.
When you first mentioned your issue, first thing that came to mind was fuel cut. But apparently you know the difference between that and a ignition problem.
Another thing you should be checking for is boost leaks. Its real easy to do, just need a compressor and a couple of plumming parts u can pick up from home depot.
PM me for details if your interested.
#17
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just ordered up a set of the ngk's everyone uses successfully on on the 1jz/2jz gte's, drive shaft is out for balancing, no test runs till the new plugs are in and the shaft is back in. Will update soon.
Kevin
Kevin
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like i said i ran 15lbs n afr was rich as hell but it lead to issue, any one that know about running a boost cut defender on a 1j should know this, wish i did before
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my fault, I have a boost controller, manual type. not very good, but able to control pretty accuratly and repeatedly. My intention is to pick safc and more complex boost control (high/low) when I have all these little kinks worked out. Dont really see much reason to start tuning when I have a msfire already. plugs are on the way so we will see. the plugs in place cameon engine and were denso iridium gapped at .45 (prev owner prob not a member of cl) so my guess is this is where my problem is, barring that I would have to assume coil pack at this point.
what went wrong with your engine? rod? detonation related? was your afr faulty?
what went wrong with your engine? rod? detonation related? was your afr faulty?
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my fault, I have a boost controller, manual type. not very good, but able to control pretty accuratly and repeatedly. My intention is to pick safc and more complex boost control (high/low) when I have all these little kinks worked out. Dont really see much reason to start tuning when I have a msfire already. plugs are on the way so we will see. the plugs in place cameon engine and were denso iridium gapped at .45 (prev owner prob not a member of cl) so my guess is this is where my problem is, barring that I would have to assume coil pack at this point.
what went wrong with your engine? rod? detonation related? was your afr faulty?
what went wrong with your engine? rod? detonation related? was your afr faulty?
while your changing ur plugs take a look at ur coil boots, thye have a tendency to crack and arc out (if they are a bandaid fix is to electrical tape the the shaft of the coilfrom the top all they way down).
as far as a/f it was in the 10s or tops low low 11's, after speaking to some shop that specialize in 1jz, it was clear that the stock set up cant realy compensate past 12-13lbs. (the top of the piston started meltin, nothing crazy but 3 n 4 had minor signs) nvr though id be rebuilding it this soon lol.
Last edited by $C300; 10-05-09 at 12:20 PM.
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ok, littlel update, swapped the plugs for ngk bkr7e(.028) and when i had them out i inspected all coil packs, one had small crack near the boot. taped the **** out of it, put boot back on and again taped the **** out of the whole thing. put it all back together, feels like an intermittent issue now (missing) sometimes yes, sometimes no under full throttle, sometimes it doesnt boost over 12 (1-2 gear) but sometimes (4th gear) i can boost all the way to boost cut. the boost cut is like a smack in the face, immediatly after i lift off throttle after hitting boost cut, it starts to miss again. its feaking weird. i think i have a bad coil pack (at least one) and some boost leakage somewhere preventing me from building 14 in 1-2 gear pulls (usually hits 12-13) this sound right to the 1jz peeps out there?
#22
ok, littlel update, swapped the plugs for ngk bkr7e(.028) and when i had them out i inspected all coil packs, one had small crack near the boot. taped the **** out of it, put boot back on and again taped the **** out of the whole thing. put it all back together, feels like an intermittent issue now (missing) sometimes yes, sometimes no under full throttle, sometimes it doesnt boost over 12 (1-2 gear) but sometimes (4th gear) i can boost all the way to boost cut. the boost cut is like a smack in the face, immediatly after i lift off throttle after hitting boost cut, it starts to miss again. its feaking weird. i think i have a bad coil pack (at least one) and some boost leakage somewhere preventing me from building 14 in 1-2 gear pulls (usually hits 12-13) this sound right to the 1jz peeps out there?
Im about to change to a different set of plugs to see if that helps. I have some platinum NGK's here (the ones that aaron recommends on driftmotions website). They have the thin tip so you cannot gap them and the fact that they are platinum may also be a reason. Im throwing in some NGK 4644's and if that doesnt work, im going to keep making the gap smaller and smaller untill it resolves it. If that doesnt work, im probably gonna buy 1 new coil and replace each coil 1 by 1.
BTW, I have a 1jz as well.
Mods:
Intake, Frontmount, 3" downpipe, no cat, 3" exhaust all mandrel, no electronics, goes to around 13psi with exact same issues you described. During the day it feels better so im guessing the colder air during the nights are causing the spark to blow out. Well see......
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ok, littlel update, swapped the plugs for ngk bkr7e(.028) and when i had them out i inspected all coil packs, one had small crack near the boot. taped the **** out of it, put boot back on and again taped the **** out of the whole thing. put it all back together, feels like an intermittent issue now (missing) sometimes yes, sometimes no under full throttle, sometimes it doesnt boost over 12 (1-2 gear) but sometimes (4th gear) i can boost all the way to boost cut. the boost cut is like a smack in the face, immediatly after i lift off throttle after hitting boost cut, it starts to miss again. its feaking weird. i think i have a bad coil pack (at least one) and some boost leakage somewhere preventing me from building 14 in 1-2 gear pulls (usually hits 12-13) this sound right to the 1jz peeps out there?
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Just a word of advice before anyone starts spending unnecessary money or wastes their time play with your spark plug gap start with .028 and decrease by .002 each time if previous didn't work
I had mine gapped at .025 when I had my twins on
Big thing to blame is our old and cracked oem coilpacks
After had them set at that gap I didn't have a bad ignition break up anymor
Just my 2 cents
I had mine gapped at .025 when I had my twins on
Big thing to blame is our old and cracked oem coilpacks
After had them set at that gap I didn't have a bad ignition break up anymor
Just my 2 cents
Last edited by sc300bigtx; 07-26-11 at 02:21 PM.
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Run copper plugs If your turbo
Iridium better when your na
Copper plugs won't last as long but they are only like $2-3 apiece
And if anyone ones having ignition break up problems
I would tape up your coilpacks and then play with your spark gap
Taping them is only a bandaid but most ppl will not break down and spend the money for new ones
I personally bought supersparks cause I went single and I dont want to have to worry bout plugs anymore lol
Iridium better when your na
Copper plugs won't last as long but they are only like $2-3 apiece
And if anyone ones having ignition break up problems
I would tape up your coilpacks and then play with your spark gap
Taping them is only a bandaid but most ppl will not break down and spend the money for new ones
I personally bought supersparks cause I went single and I dont want to have to worry bout plugs anymore lol