performance
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Driver
Joined: Apr 2011
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From: washington
performance
so i don,t know if anyone has had this problem but. I did the aristo swap into my 92 sc 300 and have the soarer R154 trans and everything runs ok when i start it. and will idle ok but when i try rev it up it will run rough and when i try to put under a load and drive it wont go into boost and it runs very rough but other then that everything looks ok. any ideas anyone 
Thread Starter
Driver
Joined: Apr 2011
Posts: 151
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From: washington
yeah i have done all that its got to be something more technical then that. i think it's got something to do with either map sensor or tps i pulled a voltage from the tps and i only get 3.2 volts when i should be getting a 5 volt reading. tweaked made the harness so i'm hoping that everything that was done should be done. there is a wire or two at the ecu that when i have it running i can jiggle a wire or two and it starts to run a little funky like its misfiring bot when it was running and idling fine it still would not boost past 3000 rpm's
^ dead on advice.
Also, you might wanna make sure timing is correct (crank pulley at 0, cam marks at the top matching their marks). But the fact that you can jiggle the harness and change the way it runs means there are problems there though not necessarily a problem that will solve THE problem.
When you hit that wall where it starts running crappy what is the AFR? And also does it start building boost when trying to rev through the breakup in neutral? If so I'd check timing.
Also, you might wanna make sure timing is correct (crank pulley at 0, cam marks at the top matching their marks). But the fact that you can jiggle the harness and change the way it runs means there are problems there though not necessarily a problem that will solve THE problem.
When you hit that wall where it starts running crappy what is the AFR? And also does it start building boost when trying to rev through the breakup in neutral? If so I'd check timing.
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From: SC
If you think the issue may be in the harness, you can always send it back for us to inspect. If there is in fact a problem, we'll cover shipping both ways. That's what our lifetime warranty is there for 
Just give us a call, 800-533-6775
Joshua
Just give us a call, 800-533-6775Joshua
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Nobody asked if he has any OBD codes??? have you checked your check engine light??
You say your not able to boost over 3k? Sounds like a bad map sensor or possible an ignition signal break which would cause a code 14.
Also you say if you jiggle a certain wire or two at the ecu you notice a difference? Wouldnt you want to identify exactly which wires those arE?
CHECK YOUR OBD THATS WHY TOYOTA INTEGRATED IT INTO THESE CARS
edit: and no.... not only if your check engine light is "on" CHECK THE DAMN CODES
You say your not able to boost over 3k? Sounds like a bad map sensor or possible an ignition signal break which would cause a code 14.
Also you say if you jiggle a certain wire or two at the ecu you notice a difference? Wouldnt you want to identify exactly which wires those arE?
CHECK YOUR OBD THATS WHY TOYOTA INTEGRATED IT INTO THESE CARS
edit: and no.... not only if your check engine light is "on" CHECK THE DAMN CODES
Thread Starter
Driver
Joined: Apr 2011
Posts: 151
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From: washington
i really don't wanna send it back in again i wanna drive it this summer. and i did check the obd for codes. and ill have to go get them tonight and post them up for i don't remember them off hand right now. But i do remember one and it was 47 and it has to do with the tps but not sure what one and since the one i do have plugged in i replaced it. but it did not change anything so next has to be the map sensor. or something along that line. and at the ecu in the 80 pin plug in the problem on the wires when i juggle the very first top wire on the left i get what sounds like a misfire. its that wire or one very close in that area not to sure really on what wire yet but hope to narrow it down without having to send it in. tweak dose a very good job just sometimes things do happen but they have taken very good care of me on this harness so i have no worries if i have to send it back. i just don't really want to have to remove this harness again it's a very big pain in the *** getting it out
Thread Starter
Driver
Joined: Apr 2011
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From: washington
anyone have a extra map sensor for sale that i can try i really don't wanna go buy a new one that so way over priced. unless you guy's know of a different lexus i could find the same one on in a junk yard ? maybe a GS model ?
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Driver
Joined: Apr 2011
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From: washington
well ok i did some more research and found out that the code i am getting is 31 and it has to do with mass air flow circuit ? dose this motor need a afm sensor also? because when i got this motor i didn't remember seeing a plug in for it
Thread Starter
Driver
Joined: Apr 2011
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From: washington
Intake Air Volume - AFM sensor
Intake Air Temperature - IAT sensor
Engine Speed - Crank Position sensor
Manifold Air Pressure - MAP sensor
Engine Coolant Temperature - ECT sensor
Exhaust Oxygen Content - O2 sensor
this is the list of sensors i need to run this motor right anyone ?
Intake Air Temperature - IAT sensor
Engine Speed - Crank Position sensor
Manifold Air Pressure - MAP sensor
Engine Coolant Temperature - ECT sensor
Exhaust Oxygen Content - O2 sensor
this is the list of sensors i need to run this motor right anyone ?
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