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Discussion Starter · #1 ·
A saga of mine, trying to get that uneven RPM under control, disassembled the throttle body and BCDD and cleaned everything;Result? same problem,PLUS the idle won't go down 2000 someone help me with this before i give up and go to the junk yard, and get a pair of SU's!:^)
Stan.
 

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Stan,
Couple of things. Follow your throttle rod all the way to the front of the engine.
1) There is a diaphragm looking thing there that, if it is misadjusted or sticks in the extended mode, can cause your throttle to stay high.
2) there is an idle adjust screw there to. You need a mirror to look at it from underneath in order to even see it. The Haynes manual and Nissan service manual describe it and its location. That can be used to adjust your idle down.
3) There's a spring loaded adjusting screw on the top of your intake manifold right at the inlet of the inlet hose to your air regulator. You can use it to affect idle speed too.
Give these a try. One or all of them will get you where you need to be.
Phantom
 

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Discussion Starter · #3 ·
Thanks,Phanthom,the diaphragm on top of the throttle body was not attached to anything, so i took it off it just hung there! the spring loaded screw on the body is in all the way, still 2000,
Haven't tried the BCDD adjust nut, it's a BITCH to get to! will try, but the RPM uneventness(!)is ,methinks,a vac leak,used to just hiss while idle, untill i checked and replaced the vac lines to the dis. and BCDD.(can't wait to get a flat top block-N42 head, 10:1 comp., cam, SU's, ECT.ECT...) :^) any thoughts?!
 

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Discussion Starter · #4 ·
> Thanks,Phanthom,the diaphragm on top of the
> throttle body was not attached to anything,
> so i took it off it just hung there! the
> spring loaded screw on the body is in all
> the way, still 2000,
> Haven't tried the BCDD adjust nut, it's a
> BITCH to get to! will try, but the RPM
> uneventness(!)is ,methinks,a vac leak,used
> to just hiss while idle, untill i checked
> and replaced the vac lines to the dis. and
> BCDD.(can't wait to get a flat top block-N42
> head, 10:1 comp., cam, SU's, ECT.ECT...) :^)
> any thoughts?!
We sell this valve assembly for 30.00+ shipping, sell them all of the time. I have never tried to disassemble, and clean them, because of having hundreds of working ones in our yard. If you want one, please call. Usual symptoms are, rpm stays up
, or stays up after car decellerates, sometimes all the way to stopping.
Joe 1-800-533-5659
 
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