RB25DET Will Not Idle After Rev

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Posts: 12
Joined: Mon Dec 30, 2019 5:28 am
Car: 1994 Nissan 240sx RB 25 DET swap

RB25DET Will Not Idle After Rev

Postby [email protected] » Wed Sep 23, 2020 5:18 pm

Hope someone can help me with this frustrating situation. My 240 SX with an RB 25DET swap starts perfectly idols nice and smooth from cold start to warm up but then when you rev it and release the gas pedal it will not re-catch the idle and it sputters and dies. I adjusted the throttle position sensor to read .48 V, replaced the IAC .
When I turn the screw in and out it raises and lowers the idle as it should, but again, when you give it a rev and release it sputters and dies. When I start it back up it goes right back to a nice idle again.
at times I hear a "click click" eminating from what looks like a two inch long , large diameter hex bolt attatched to the head , towards the front of the car . It has a two wire connector attatched to it's end and that is where the clicking is coming from. car has been checked for vacuum leaks and I cannot find any.
I sure hope this sounds familiar to somebody have not been able to drive the car for sometime now thank you so much everyone.


ca18det_boy
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Location: Homestead, FL

Re: RB25DET Will Not Idle After Rev

Postby ca18det_boy » Mon Sep 28, 2020 10:49 am

I'm pretty sure the two wire bolt you're referring to is nothing but the VCT. Can you give some more information like which series RB it is, wiring harness, recent maintenance, ecu, etc? That would help a lot in trying to help you.

[email protected]
Posts: 12
Joined: Mon Dec 30, 2019 5:28 am
Car: 1994 Nissan 240sx RB 25 DET swap

Re: RB25DET Will Not Idle After Rev

Postby [email protected] » Tue Sep 29, 2020 2:54 am

I checked the service manual and it says that the throttle sensor with throttle plate closed should be reading 0.4 to 0.5 ohms, my sensor is reading about 1400 Ohms and the sensor V reads .48v.
Maybe I should try to adjust it to .4 ohms and dissreguard the v reading ?

ca18det_boy
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Posts: 1380
Joined: Wed Dec 24, 2003 10:47 am
Location: Homestead, FL

Re: RB25DET Will Not Idle After Rev

Postby ca18det_boy » Tue Sep 29, 2020 6:42 am

TPS.jpg
Heya you still didn't answer my questions to better help you. I looked back through the FSM and I didn't see anything about ohms. There's the requirement that the TPS needs .6V (closed) - 4.0V (open).

ca18det_boy
Moderator
Posts: 1380
Joined: Wed Dec 24, 2003 10:47 am
Location: Homestead, FL

Re: RB25DET Will Not Idle After Rev

Postby ca18det_boy » Tue Sep 29, 2020 6:45 am

Did you just swap this RB into your S14 and are you using a blow off valve?


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