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I got a feeling its your fuel pump or full voltage not going to pump. One time my old 1j was having similar issues and at idle it was just fine but when it needed more fuel, it would lean out. Turned out one of the wires was rusted and not supplying full voltage to fp.
 

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Discussion Starter #23
After putting in new fuel and disconnecting the speed wire from the ecu, now I'm only going lean on boost, and fine (in the 14's) in vacuum. Any boost will take it to 16-17 and then off the reader
 

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slowest restoration ever
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could be ecu anyway

From what I've read there's no guarantee the caps aren't bad in the ecu just because they aren't visibly bad.
you might want to try having those replaced.
 

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Your fuel pump ECU is not giving you 12v, bypass that crap so you run 12volts all the time, PLUS when I had this issue in a customers car, it was a dying FUEL PUMP!!!! same exact behavior.
 

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Discussion Starter #27
Problem fixed

PROBLEM FIXED!! Wow! Needed new fuel pump, but I cant say it wasn't also coilpacks as I installed brand new denso coilpacks (old ones had cracks on 4 of 6) and had noticed a big difference after that too. Installed a Kyosan denso 300lph pump from densofuelpump.com. She pulls amazing, im screeching tires in 3rd doing nothing!! Also had recalibrated tps, new bkr7e plugs, checked for boost/vacuum leaks(found none), I gotta say though, the wideband was so critical in this, I would have done some serious damage if I didn't have the wideband in there! And the fuel pump ecu was already bypassed, was getting 13v constant. Before this I went full lean coming on ANY BOOST!, now there is no hickups, hesitation, bogging, and its boosting well over 1 bar!
 

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Discussion Starter #28
Fixed! It was a dying fuel pump, drove just fine in vacuum, but any boost and it went full lean and would bog/loose all power

Your fuel pump ECU is not giving you 12v, bypass that crap so you run 12volts all the time, PLUS when I had this issue in a customers car, it was a dying FUEL PUMP!!!! same exact behavior.
 

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I'm having a similar issue but my 1jz runs on maf sensor. When in open loop (cold engine) car drives boosts and pulls great, but once in closed loop (warmed engine) it bogs hard right as I enter 14% airflow (2300rpm) partially increased throttle.
 
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