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Discussion Starter #1
Hi.I'm new to this forum and supra world so I'm wondering if anyone can tell me exactly procedure for adjusting throttle stop screw on 2jzgte.Mine is undone all the way and I'm pretty sure that's not right.Looked everywhere but couldn't find anything for 2jzgte,but I did find for some other Toyota and it said when you undo it all the way ,screw it back just to touch the plate and then give it 1/4 turn.Is it same on Supra?
Thanks in advance
 

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Boost Junkie
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Do you have access to the factory service manuals? There is a specific procedure you must follow in order to insure voltage readings to the ecu are correct.

Steve
 

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I wanna go fast!
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Do you have access to the factory service manuals? There is a specific procedure you must follow in order to insure voltage readings to the ecu are correct.

Steve
This. There are a number of different components on the throttle body that need to be set properly. 4 if I recall correctly. I suggest adjusting I'm the following order.

1. Throttle opener. It's the vacuum operated device on the left side of the throttle body if looking at it from the front of the car. When throttle plate actuator assembly comes off this component, rpm should be within a certain range.

2. Dashpot. This is just a spring loaded component that prevents the throttle from slamming down too hard when you release the throttle. Again, when coming off this device, engine speed should be within a certain range.

3. Throttle plate itself. If you are at full temp idle you should be in the 650 range. I generally go a bit higher because it's generally tough to make engines idle great that low.

4. Tps. This almost takes 4 hands to perform but essentially you need to pull a vacuum on the throttle opener, stick a feeler gauge between the adjuster screw and the throttle plate arm, measure resistance on 2 terminals of the tps and adjust accordingly. Then you perform the same procedure with 2 different size gauges to confirm your adjustment.

It's of intermediate difficulty but it is very time consuming to get it 100% correct. You will find that easy adjustment can affect the other somewhat so multiple passes may be necessary.

Mkiv.Com has a 95 supra tsrm that contains the procedure. Google search '95 supra tsrm' and you will find it. Same procedure applies for all years with throttle cable actuated throttle bodies. If running fly by wire, I don't know, lol!
 

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Discussion Starter #4
Thanks for quick reply.Here is little background.This is JDM 1994 Supra NA that my buddy bought and did Aristo GTE swap.He couldn't get it running for 2 years and got pissed off and sold it to me.So far he did cold air intake,3" exhaust front to back,front mount intercooler,12v fuel pump mod,adjustable fuel pressure regulator.I added new plugs,coils,boost gauge,aem afr gauge x series,HKS BOV,couple of vsv' s.I tried to adjust tps as per TRSM but I don't have that throttle valve (maybe because it's from Aristo).So I backed off that throttle stop screw all the way to close the plate and then adjusted tps and I got the car running but it's very rich (8s and 9s on afr) unless I step on it and I get 5,6 psi or more of boost,then I'm in 12s and 13s.Also if I step on gas pedal very quick I get hesitation and backfire but if I keep pushing slowly or medium speed I can get it to boost to 13,14 psi and it goes pretty good.
Another issue is every time when I start cold,car runs at about 2000 rpm and then gradually comes down to 700-800rpm,but if I start warm or hot my idle is up and down from 1000 to 2000 rpm (after being at 2000 rpm for about 20 seconds) and it calms down only if I take it for ride with couple of heavy loads.Burns about 30 l of gas per 100km.And that's every day driving around town.So I tried with aftermarket coils and new ngk copper spark plugs and used MAP sensor and new temperature sensor and it's still the same so I have another used TPS that I want to try but I want to make sure my throttle plate is where it should be before any TPS adjustment.Sory for a long story but I thought something in there might be important
 

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Discussion Starter #6
So I replaced and adjusted TPS and i got no more hesitation on hard acceleration.Still running rich like crazy and my idle is hunting up and down.I checked all wiring between ECU and IACV,everything seems ok.I think I'm going to find another IACV to try and also new O2 sensor.Thanks again for advice
 

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Coolant temp for the computer try unplugging it and staring The car and see how it runs. I would guess from the description it thinks it's in Antarctica all the time
 

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Discussion Starter #9
Yes my MAP sensor is plugged and I tried different one from a car that was supposedly running good.
I thought that too about temp sensor so I replaced it with a new one.I also checked wiring from temp sensor to the ECU and it checked OK.I'm starting to think this ECU could be bad cause it lookes all banged up probably from shipping when it came hanging on the engine :)
 
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