1JZ down on power

MK3MKB

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I had another thread here---> http://www.supramania.com/forum/threads/1jz-boost-leak.249031/ trying to diagnose a boost leak I couldn't find, turned out to be an exhaust leak but I still have the same problem I've been having since buying the car. I think I've evolved past a boost leak issue, prompting a new thread. I thought it was a boost leak when I bought it and easily fixed so I didn't pass up the deal. My car is a 1993 Toyota Chaser, 1JZ-GTE non-vvti, automatic. 117,000 kilometres. I really want to get the car squared away and start enjoying it more.

The issue I'm having are:
-Low power
-Struggles to pull up hills
-Will not shift past 4,500 RPM (unless its in third, and will rev to 5,250 and no further)
-Sometimes spits some black smoke when you punch it
-When cruising and you try to floor it, it will rev up like it down shifted but not take off, waits a second then actually down shifts and starts accelerating
-will not break traction at all
-intermittent no start

So far I have checked:
-boost leak checked the entire system at 14 psi, found 2 very small leaks and repaired them
-verified timing
-verified turbos good
-verified waste gate actuators good
-swapped recirc valve
-disabled recirc valve (temporarily, it's currently working)
-ohm tested crank sensor, and front cam sensor, found good
-pulled codes, had code 14 but no CEL
-replaced igniter
-sent ECU back to rebuild shop to be looked over, he didn't find anything but went ahead and replaced the injector caps
-checked compression, found good
-checked boost pressure with gauge, at best its making 2 psi
-TRC light is on, so I pulled ABS relays in case it was in limp mode, no change
-unplugged TRC stepper motor because of light, verified it is open
 

MK3MKB

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sounds like blow turbski's. Smoking when you punch it, 2 psi. How were the turbo's verified?
Smoke looks to me like when an engine is running rich. It’s black, not blue. Turbos were swapped with a known good set. No change in performance.
 

Abe's 1987

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If i remember righrt doesn't black smoke mean to much fuel being burned?
 

MK3MKB

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May have found something. When I swapped turbos it came with another set of piping for the turbos. I had my original set powder coated. I was disassembling today and found all 4 of the turbo flanges had oil on them. I reused the metal gaskets that came off. It was edge to edge on both sides of the gasket but wasn’t dripping wet. My thought here is if oil is getting past the gasket, so is air. Tomorrow when I reassemble I’m going to use the metal gaskets with black RTV on both sides.

Also, a couple weeks back I saw a post on Facebook about the rubber connectors on the intake where it splits to go to either turbo can swell internally and block flow. I pulled mine and they were swollen. replaced those and gained back some RPM range, but still not all the way to redline. Also feels a little less down on power.