The infamous 1jz breakup: tried alot, getting no where
- Thread starter *james*
- Start date
The new plugs and tightening the ground didn't work still hitting cut at 4k. Its almost like. rev limiter sometimes it will go past 4k but only to like 4200 or 4500 but that's rarely. sometimes its like a rev limiter bounces off 4k or it just feels like a boost cut and I loose acceleration for 2 seconds then it comes back to life.
Sounds like it could be fuel cut if it lasts for 2 seconds. Are you on stock twins or what? What kind of injectors are you running? Just look at the color of them. If stock twins you will need to check all your vacuum lines, especially the wastegate, if one line has a leak or disconnected you could be overboosting and hitting cut. What are all the mods and what type of exhaust?
driftmotion intake and front mount, on stock twins. I think my vacuum is messed up and the injectirs I think are yellow. I have a 3inch hks dragger. I need to figure out what the vacuum lines go to. there is like three on the manifold looped together pretty much to the fuel pressure regulator.
here is the picture I took of the tee line. the line runs from two different ports then goes to the fpr. should I only have one vacuum source going to the fpr?
Anyone have an idea what to do about the vacuum lines? I was thinking bout just running one to the fpr and use the other for a boost gauge since I have no idea where my gauge hooks up at it obviously isn't around the intake manifold maybe I should find out where it is located at.
kornfedmk3;1922158 said:
here is the picture I took of the tee line. the line runs from two different ports then goes to the fpr. should I only have one vacuum source going to the fpr?[/QUOTEyeah that's not right lol. Ok I would run a single line to your FPR instead of having all of those other lines. I'm guessing that last line runs behind your valve covers to your BOV, but i'm just guessing. (That line is the last port on my mani for mine. I'll go out and have a look at mine later as I drove it to work.
I also agree with Tura
Can you post another photo of the rest on the mani?
so I decided to check the ecu and as I'm unplugging it there is so many random ass plugs around the loom its not even funny there is a couple with only a few wires in the plugs and all the other ones look like they were cut out. I don't know why its like this but I'm pissed now cause I have no idea what its for. the picture that's above is a ecu plug, plug three from left to right and seems that pin 29 or 32 seems like it was ripped out or something can someone please help verify what this pin is and what they do. and if that is my 4k rev limiter/ cut problem is.
also when I punch it right when it hits 4k it does its little rev limiter thing I watched the wideband and as soon as it does it the gauge goes directly to no reading like its going really lean. also when it happens the CEL comes on but goes away in a minute. why?
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Picture you have there shows the C85 ECU plug. From left to rigt you have PFC, Engine Checklight (CEL),M-REL (main relay) and NEO (Speed output to Traction Control ecu).
Take a Picture of the other ecu-plugs please, especially the C86 plug (You have a jzz30 Soarer or Chaser jzx90 ecu).
Take a Picture of the other ecu-plugs please, especially the C86 plug (You have a jzz30 Soarer or Chaser jzx90 ecu).
today I finally got the vacuum lines figured out the only question I got is the one way valve in the picture that is screwed into the manifold does that go to the map sensor? the map sensor was originally hooked up to the port above it so I switched them around cause in the vacuum diagram it looks like the one way valve suppose to go to the map sensor. I also hooked up the boost gauge to a port on the backside of the manifold and it now reads correctly thank god! currently running 10psi till I hit this stupid cut.
I also opened up the ecu and looked around and it looks great no leaking caps or anything. the IGF pin looks like it is secure and connecting right. My next step is definitely swap out the igniter for a known good one just got to find one around me. Also the ecu is a m/t not a a/t. Does anyone else think of anything I should check besides the igniter I think that is the last step to check before the full wiring.
kornfedmk3;1926151 said:
today I finally got the vacuum lines figured out the only question I got is the one way valve in the picture that is screwed into the manifold does that go to the map sensor? the map sensor was originally hooked up to the port above it so I switched them around cause in the vacuum diagram it looks like the one way valve suppose to go to the map sensor. I also hooked up the boost gauge to a port on the backside of the manifold and it now reads correctly thank god! currently running 10psi till I hit this stupid cut.
I also opened up the ecu and looked around and it looks great no leaking caps or anything. the IGF pin looks like it is secure and connecting right. My next step is definitely swap out the igniter for a known good one just got to find one around me. Also the ecu is a m/t not a a/t. Does anyone else think of anything I should check besides the igniter I think that is the last step to check before the full wiring.
The hoses look right, however it looks as if your CPS sensor might be leaking a little bit.
if your hitting boost cut at 10 lbs its prolly spiking over 12.5 lbs. is it an EBC or MBC? I'd just double check theirs no leaks in the vacuum system and the reason some of your wires are cut is because the ecu is for another car.
No it stays right at 10 no spiking at all. even if I free rev it it still does it so I know its electrical.
That valve on the manifold is a filter not a check valve. The manifold diagram from Toyota shows the map sensor going to it but I have mine running without and the VSV going to the filter.
I had a recent issue simular to yours and it was the front cam sensor plug wasn't locked on. The old harness lock had broken off in the CPS and prevented the new plug from locking on but it was intermittent and yes they like to leak oil. I also popped a 13 code which you havn't had.
You say it goes lean when this happens, sounds like a fuel issue.
Do you have a way to check what the fuel pressure is?
Do you know what fuel pump is in the tank? If the car was originally an NA and its the stock NA fuel pump still in the tank that would be your problem.
I had a recent issue simular to yours and it was the front cam sensor plug wasn't locked on. The old harness lock had broken off in the CPS and prevented the new plug from locking on but it was intermittent and yes they like to leak oil. I also popped a 13 code which you havn't had.
You say it goes lean when this happens, sounds like a fuel issue.
Do you have a way to check what the fuel pressure is?
Do you know what fuel pump is in the tank? If the car was originally an NA and its the stock NA fuel pump still in the tank that would be your problem.
car is a turbo model with stock pump. the only reason I don't think its fuel related is because it does it free reving under no load. would the coil pack clips having the lock part broken cause this? I make sure it is connected tightly but sonce the lock on is broke would that be a problem I got like 3 clips like that
I made a video let me know what you think. also I was in neutral coasting and I went full throttle and it hits a cut sounds like a rev limiter.
