2JZGTE swap this summer...

still did not solve the XXXXing brake problem (((
i tried another check valve, tried changing the whole vacuum line from intake manifold to the brake booster, including the check valve, this did not help....
also noticed, when i stop the engine, i can hear a hissing sound from around the brake booster for a couple seconds. and the brake pedal becomes hard immediately after stopping the engine..
 

If you are hearing a hissing coming from inside the vacuum booster the is a small hole in the booster diaphram.
To test this theory disconnect the vacuum hose coming from the manifold and connect a might-vac or similar testing tool. Pump up and pull a vacuum on the booster. If you can't pull over 28" there is a definite leak in the diaphram.
 
finally solved!
the booster was loosing the vacuum through the hole for some XXXXing sensor in it... by the way, does anybody know, what is this sensor for?
 
i still don't have the warm up RPM though.. when the engine is warmed , e.g. after driving some distance, it holds idle RPM as it should.
but in the morning, or after any long stop, the engine doesn't start. it starts for a second, gets about 700rpm and immediately chokes. i have to sit inside and hold the accelerator pedal to warm it up. after the temp gauge shows about 100, it doesnt choke, but rpm still very low , abou 400-500, the engine shakes.
the higher the temperature, the higher the RPM... but must be otherwise.
maybe there is a solution ?
 
I still think something is wrong with the IAC or it's control circuit. That is the components one freaking job. Control rpms at idle. It's not doing it.

My 2J fires up to >2000 rpm when cold and slowly comes down to 750-900 over a minute as the engine and oil warms up.
 
Last edited:
Maybe it is a JDM control? WHat I do know is it takes my Son's Subi around a minute to come down to the final idle point. I went to Subaru on it and was told "normal operation left over from the JDM".

I fully realize yours is not a Subi but, isn't the ECM JDM in origin? Just asking...
 
child9 said:
I still think something is wrong with the IAC or it's control circuit. That is the components one freaking job. Control rpms at idle. It's not doing it.

My 2J fires up to >2000 rpm when cold and slowly comes down to 750-900 over a minute as the engine and oil warms up.
Click to expand...

i disassembled the idle control valve and checked it according to the manual, it works properly both ways, opens and closes...

can any of this vacuum hoses, or the 17650 valve cause trouble ?
170220.png
 
o-gauge-steamer said:
Maybe it is a JDM control? WHat I do know is it takes my Son's Subi around a minute to come down to the final idle point. I went to Subaru on it and was told "normal operation left over from the JDM".

I fully realize yours is not a Subi but, isn't the ECM JDM in origin? Just asking...
Click to expand...

mine is fully JDM, the engine itself and the ECU also, but that's not the reason, have some cars around with the same engine installed in stock, and they work as they should at the idles...
 
You could try adjusting the throttle body screws to hold the butterfly open slightly and just bypass the IAC if you haven't already. I would try to eliminate the IAC as being the problem.
 
What about the CTS that goes the ecu? DO you know for a fact that it is good?

As far as all the vacuum hoses go, I couldn't tell you. I eliminated most of that when I got rid of the twins.
 
Love love love. I gotta say I feel your Jeep is clean and crisp and those things are important to people like me. GOOD JOB MAN. How's the idle situation Burik?
 
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