Unique 1jz 3k rpm breakup
- Thread starter Albert
- Start date
gurley0916;1615761 said:
haha well i found a guy here in tucson with a 1jz block and i think it may still have the FPD i can ask him for if it'll work on your 2jz
I can get my old one pack, Albert would need the 1j one for him. Were gonna try another FPD line from driftmotion and see if the 2j will have the problem. If it does ill let you know if I need it or not
Also you dont need to use a 2j FPD you can go back to the stock 1j...Albert just used mine cause it was off my motor and he didnt have his old one.
Also you dont need to use a 2j FPD you can go back to the stock 1j...Albert just used mine cause it was off my motor and he didnt have his old one.
Subscribed - I have a Very Similar Issue.
***not Hijacking***
My car Free Rev's Fine and will Rev HIGH, no Break up..but yet whenever it Gets to 3000rpms on the Dot..it goes damn lean on my AEM Wideband (15-16 afr) but continues to Rev Fine.As soon as its Past 3000,AFR's Goes back to how it should be.
When I'm driving and under load - light to moderate pedal pressure,..It will lose power a little when it hits 3k...but Wakes Right up at 3100+/- and Is Perfect throughout.
Idle is perfect..no Smoke (Running open Downpipe),No Nothing.Fires right up each time.
I have found when I'm in 1st Gear and Just Cruising and I'm already past 3k and slow down,..when I accel back up slowly and over 3k again it Dosen't do the lean Thing.Its Weird.
No other Quirks to this setup I have what-so-ever.I can't run codes as I have a Custom Cluster with no CEL - I used the OEM cluster and Put my own gauges in it.So No help there.
---what I've done so far---
-Re-gapped NGK 3330 Coppers to .25 (from 35)
-Fuel Pressure to 43psi (no vac)
-Checked another set of 6 Working Coil's and MkIV Map sensor
-Adjusted SAFC to get more Fuel at 3000rpm and that Helps but even at +6 on that NEpoint - it still gets lean but I think its Helps.
-Checked ECU again by opening and The inside Is perfect!
-Injectors were Mapped and Cleaned by Deatshwerks
I've order some parts to allow me to hook up my Old FPD and test it to see if mines the same as your Fix...but I also Just scored a Used MapECU to Fine tune the Engine anyway.Should be able to get it out with that.
Car and Setup:
SC400 with SOARER 1JZ/R154 swap,JDM 440cc,Dmotion 57trim single Turbo,Dmotion Dampner BYPASS,Dmotion Aeromotive FPR with hardlines,Walbro - 12v fuel pump mod,SAFC with patch Harness AEM Uego wideband (mounted right behind factory o2 sensor.
*Engine was Cleaned and Everything Maint done before install (Tbelt,MKIV water pump,Hot tanked Head,OEM Headgasket,Valve Stem seals,Rear main,cam,crank seals etc etc.You name it.
No Engine harness wiring was cut on my Swap - I was able to Run the harness with Only extending the Body Plugs (at the Kick panel) a tad and I've double Checked All that.
ECU Insides:
No caps busted,leaking,anything.All Looks great.Was gonna send it out but Don't think there is a reason to.
Heres the Engine:
***not Hijacking***
My car Free Rev's Fine and will Rev HIGH, no Break up..but yet whenever it Gets to 3000rpms on the Dot..it goes damn lean on my AEM Wideband (15-16 afr) but continues to Rev Fine.As soon as its Past 3000,AFR's Goes back to how it should be.
When I'm driving and under load - light to moderate pedal pressure,..It will lose power a little when it hits 3k...but Wakes Right up at 3100+/- and Is Perfect throughout.
Idle is perfect..no Smoke (Running open Downpipe),No Nothing.Fires right up each time.
I have found when I'm in 1st Gear and Just Cruising and I'm already past 3k and slow down,..when I accel back up slowly and over 3k again it Dosen't do the lean Thing.Its Weird.
No other Quirks to this setup I have what-so-ever.I can't run codes as I have a Custom Cluster with no CEL - I used the OEM cluster and Put my own gauges in it.So No help there.
---what I've done so far---
-Re-gapped NGK 3330 Coppers to .25 (from 35)
-Fuel Pressure to 43psi (no vac)
-Checked another set of 6 Working Coil's and MkIV Map sensor
-Adjusted SAFC to get more Fuel at 3000rpm and that Helps but even at +6 on that NEpoint - it still gets lean but I think its Helps.
-Checked ECU again by opening and The inside Is perfect!
-Injectors were Mapped and Cleaned by Deatshwerks
I've order some parts to allow me to hook up my Old FPD and test it to see if mines the same as your Fix...but I also Just scored a Used MapECU to Fine tune the Engine anyway.Should be able to get it out with that.
Car and Setup:
SC400 with SOARER 1JZ/R154 swap,JDM 440cc,Dmotion 57trim single Turbo,Dmotion Dampner BYPASS,Dmotion Aeromotive FPR with hardlines,Walbro - 12v fuel pump mod,SAFC with patch Harness AEM Uego wideband (mounted right behind factory o2 sensor.
*Engine was Cleaned and Everything Maint done before install (Tbelt,MKIV water pump,Hot tanked Head,OEM Headgasket,Valve Stem seals,Rear main,cam,crank seals etc etc.You name it.
No Engine harness wiring was cut on my Swap - I was able to Run the harness with Only extending the Body Plugs (at the Kick panel) a tad and I've double Checked All that.
ECU Insides:
No caps busted,leaking,anything.All Looks great.Was gonna send it out but Don't think there is a reason to.
Heres the Engine:
IMO I would try fixing the problem on stock ecu. Or close to it before trying to just tune it out. I have a AEM FIC and I could of tuned it out, and I did try that, it's just right as the turbo wants to spool. its cause you have to add a whole bunch of fuel at the 3k breakup... Which is pointless for your turbo...
Yup. Gonna try putting the FPD back and See if that Helps before Doing any tuning.
May Try to remove the SAFC and See what happens too.
May Try to remove the SAFC and See what happens too.
gurley0916;1616105 said:
yeah i figured that he used your because it was "readily available" but i also figured you guys would still need one in the end if the DM unit doesn't get worked out with aaron. lol either way guys let me know... but as of right now not sure when i'll be heading back up to tempe... billy hasn't finished my harness yet.
I have a very similar issue i've been trying to figure out.
1.5JZ swap MPT61 HKS 264 cams DM FPD Line, Walbro, 12vmod, 550's w/resistor, etc etc etc
I start the car, free rev to redline no problems. No smoke at all, i've hooked up my laptop and at idle my AFR is very lean, 15-22's. Full Boost 8.4-9.3.
Cruising 1-30% throttle
2500 RPMS it starts to sputter/breakup and will slightly go past 2500 with no additional throttle
30-100% It will rev to 2500 you hear it break up a little bit, while its breaking up i get 5PSI, at 3K it clears up and by 4K its at 9PSI and pulls like a bat. But the 2500 sweet spot is killing me for cruising.
I lowered my fuel pressure from 40 to 35/32 and free reving it breaks up. I put it back up to about 42/43 and it still has the problem with sputtering at 2500 rpms.
Boost gauge read -20
But FPG set at 40 w/o vac drops down to about 30ish. Is that right?
Sucks as i do not have a stock FPD to try out, i got rid of mine when i did the swap
NO codes either.
I've created my own codes to make sure the check engine light works and it does.
1.5JZ swap MPT61 HKS 264 cams DM FPD Line, Walbro, 12vmod, 550's w/resistor, etc etc etc
I start the car, free rev to redline no problems. No smoke at all, i've hooked up my laptop and at idle my AFR is very lean, 15-22's. Full Boost 8.4-9.3.
Cruising 1-30% throttle
2500 RPMS it starts to sputter/breakup and will slightly go past 2500 with no additional throttle
30-100% It will rev to 2500 you hear it break up a little bit, while its breaking up i get 5PSI, at 3K it clears up and by 4K its at 9PSI and pulls like a bat. But the 2500 sweet spot is killing me for cruising.
I lowered my fuel pressure from 40 to 35/32 and free reving it breaks up. I put it back up to about 42/43 and it still has the problem with sputtering at 2500 rpms.
Boost gauge read -20
But FPG set at 40 w/o vac drops down to about 30ish. Is that right?
Sucks as i do not have a stock FPD to try out, i got rid of mine when i did the swap
NO codes either.
I've created my own codes to make sure the check engine light works and it does.
Still haven't figured out the issue yet. I'm just shooting ideas. Would running a walbro 255lph & FPR set @ 50 w/o vac be a good idea?
Wanted to let everyone know that I put the Fuel Damper back on, and still used the hardline from Driftmotion (with a AN Fitting in place of 1 of the Banjo's) and It Totally Fixed the Problem.
Talked to Aaron and He's Right.....This Bypass is not really the problem...the line was designed For people with a Hardcore Fuel Set up..meaning Dual Pumps,1000cc etc etc.
I Just ran it Due to I hate Banjo's and Factory Hardlines Due to Removal and Ease of Installation.
Thank God I got it running right now as I didn't want to have to take the intake Mani off and Check all that STuff.
Thanks Guys!
Talked to Aaron and He's Right.....This Bypass is not really the problem...the line was designed For people with a Hardcore Fuel Set up..meaning Dual Pumps,1000cc etc etc.
I Just ran it Due to I hate Banjo's and Factory Hardlines Due to Removal and Ease of Installation.
Thank God I got it running right now as I didn't want to have to take the intake Mani off and Check all that STuff.
Thanks Guys!
Mrfairlady;1618784 said:
interesting.... I have a walbro and 550's.... figured i would be "ok". Anyone have a stock damper i can borrow?
Hi, sorry it took so long to respond, I have been so busy the last few weeks. First we were getting ready for the Marlin Crawler Rubicon Roundup, then catching up when we got back.
Originally we did intend for the 1JZ dampener bypass hose to be used by people running higher fuel pressures then stock, and requiring more fuel flow and pressure then the dampener assembly would support. But it also makes it convenient to install, and it cleans up the plumbing, so I see why people would still want it for a stock(or almost stock) setup. I have been working on 1JZ engines for about 6 years now, and the lean spot around 3k rpm was fairly common ever before we started making the bypass hose. I know the fittings on our hose are not the problem, the diameter all the way through is about the same as the stock hardline. I have done some research and I think the issue is that on some engines there may be a resonance in the fuel flow at light throttle from removing the dampener. This seems to be limited to the 1JZ only, probably due to the injection arrangement, injector pulse width, etc... I have installed our fuel line on many 1JZ engines that ran great with no issue. Since I heard nothing about it from anyone until a few weeks ago, I didn't know anyone was having any problems. Keep in mind that ignition issues are common with the 1JZ, and also people often don't use good grounds when doing their swap, not to mention bad harness or wiring mistakes, fouled plugs, bad ecu's, etc... If it truly is a problem with the dampener being removed, as the gentleman stated earlier you can use our dampener bypass hose to feed the stock dampener assembly. I will also look into making an inline adapter that will allow the use of the dampener without the original bracket and banjo bolts.
Originally we did intend for the 1JZ dampener bypass hose to be used by people running higher fuel pressures then stock, and requiring more fuel flow and pressure then the dampener assembly would support. But it also makes it convenient to install, and it cleans up the plumbing, so I see why people would still want it for a stock(or almost stock) setup. I have been working on 1JZ engines for about 6 years now, and the lean spot around 3k rpm was fairly common ever before we started making the bypass hose. I know the fittings on our hose are not the problem, the diameter all the way through is about the same as the stock hardline. I have done some research and I think the issue is that on some engines there may be a resonance in the fuel flow at light throttle from removing the dampener. This seems to be limited to the 1JZ only, probably due to the injection arrangement, injector pulse width, etc... I have installed our fuel line on many 1JZ engines that ran great with no issue. Since I heard nothing about it from anyone until a few weeks ago, I didn't know anyone was having any problems. Keep in mind that ignition issues are common with the 1JZ, and also people often don't use good grounds when doing their swap, not to mention bad harness or wiring mistakes, fouled plugs, bad ecu's, etc... If it truly is a problem with the dampener being removed, as the gentleman stated earlier you can use our dampener bypass hose to feed the stock dampener assembly. I will also look into making an inline adapter that will allow the use of the dampener without the original bracket and banjo bolts.
bigaaron;1619164 said:
Hey Aaron,
I don't see the fuel being a problem for some reason. I think its ignition but hey i could be wrong. I got my injectors clean and flow tested and it all came back good, DM AFPR, Damper bypass, and i just got the ECU recapped by you, and @ light throttle its bad and full i can "muscle" through it. I start to boost at 2K by 2500 i'm at 3-5 PSI but it just sputters (and wont boost any more) til abou 2900/3K then it continues to boost w/o sputter and by 4K wastegate opens up and it hauls ass. I've thought maybe a faulty AFPR as i got it used, bad walbro, bad coils. I set the FP to 42 PSI no vac. W/ VAC it drops down to 30PSI. When i shut the car off it goes up to about 38-40 then drops after a few minutes. AR is 8.4 to 9.3 @ full throttle 3K+
Any idea?
Coils when they were in the 1J i had no issue with sputtering but i did not have as many fuel mods, only a walbro.
untouched 1J harness, extended body plugs by DM, SAFC wired in to harness (only tapped in and map only cut wire), EA2 wired in properly, ecu has been recapped, new iridium SP added 2 weeks ago.
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