KA24de Help! Not your normal high idle - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Franzie47.LV · 03-10-2015, 09:03 PM

Ok so I'm completely new to this but I need help badly. There's the situation, I bought a 240sx in hopes to swap over my freshly rebuilt KA. Before the swap I noticed the older KA would idle at 2000rpms at a complete stop. I didn't think much of it since I was going to swap it out anyways. After the new rebuild KA was in everything was plugged in, I still had a high idle. 1500-2000 rpms every time I stopped moving. I swapped in another motor harnesses due to my old one missing the tps sensor and still nothing. Swapped ecu and maf. Nothing. I readjusted the timing several times along with the throttle plate, and cable and still nothing changed. The motor has BC cams 264, injen intake, and is stock other than that. EGR has been deleted and the IACV is fairly new. Vacuum lines are all plugged off and the rest are in good condition. No a/c or emissions. The rebuilt KA ran just a few months ago in another s13 with zero problems.

Same idle problem with two different motors and a different motor harness. I can't figure out what to troubleshoot next I've ran out of ideals that would cause a high idle that isn't on the motor itself.

I've been troubleshooting for days and I'm stumped. Any ideas anyone?

rioredstang · 03-10-2015, 09:20 PM

I would look at PCV system to see if valve is flowing too much. Also check brake booster. Have intake smoked for leaks.

Franzie47.LV · 03-11-2015, 11:30 AM

Checked the PCV system and everything is tight and seems to be in its rightful place. The booster line is clamped tight and has no cracks. Maybe the master cylinder? I double checked the timing last night and it won't start at all anymore.i just retarded the timing a hair and boom no spark seems like the coil pack shorted out.

SidewaysS13ka · 03-16-2015, 01:09 PM

Try putting the dizzy back to Oe timing and see if it will fire. If you didn't retard it with a timing light hooked up that could be your firing problem. As for the high idle. Let the car warm up and on the passenger side on the intake manifold you will see the iacv which a Philips head screw which controls idle. I know when I did my full emissions delete and butterfly delete on my de my idle went up to about 1500 when I first fired it. Had a buddy watch the tach and adjusted my iacv accordingly. Hope I helped or at least guided you to a solution.

03-10-2015, 09:03 PM	#1
Franzie47.LV Join Date: Apr 2012 Location: Las Vegas, NV Posts: 3 Trader Rating: (0) Feedback Score: 0 reviews	KA24de Help! Not your normal high idle Ok so I'm completely new to this but I need help badly. There's the situation, I bought a 240sx in hopes to swap over my freshly rebuilt KA. Before the swap I noticed the older KA would idle at 2000rpms at a complete stop. I didn't think much of it since I was going to swap it out anyways. After the new rebuild KA was in everything was plugged in, I still had a high idle. 1500-2000 rpms every time I stopped moving. I swapped in another motor harnesses due to my old one missing the tps sensor and still nothing. Swapped ecu and maf. Nothing. I readjusted the timing several times along with the throttle plate, and cable and still nothing changed. The motor has BC cams 264, injen intake, and is stock other than that. EGR has been deleted and the IACV is fairly new. Vacuum lines are all plugged off and the rest are in good condition. No a/c or emissions. The rebuilt KA ran just a few months ago in another s13 with zero problems. Same idle problem with two different motors and a different motor harness. I can't figure out what to troubleshoot next I've ran out of ideals that would cause a high idle that isn't on the motor itself. I've been troubleshooting for days and I'm stumped. Any ideas anyone?

03-16-2015, 01:09 PM	#4
SidewaysS13ka Zilvia Junkie Join Date: Feb 2011 Location: Northeastern,PA Age: 31 Posts: 334 Trader Rating: (12) Feedback Score: 12 reviews	Try putting the dizzy back to Oe timing and see if it will fire. If you didn't retard it with a timing light hooked up that could be your firing problem. As for the high idle. Let the car warm up and on the passenger side on the intake manifold you will see the iacv which a Philips head screw which controls idle. I know when I did my full emissions delete and butterfly delete on my de my idle went up to about 1500 when I first fired it. Had a buddy watch the tach and adjusted my iacv accordingly. Hope I helped or at least guided you to a solution. __________________ Leaks,Creeks,Squeaks, and other random problems. Yup you own a 240.

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03-10-2015, 09:20 PM	#2
rioredstang Leaky Injector Join Date: Jan 2009 Location: Chattanooga, TN Age: 64 Posts: 81 Trader Rating: (1) Feedback Score: 1 reviews	I would look at PCV system to see if valve is flowing too much. Also check brake booster. Have intake smoked for leaks.

03-11-2015, 11:30 AM	#3
Franzie47.LV Join Date: Apr 2012 Location: Las Vegas, NV Posts: 3 Trader Rating: (0) Feedback Score: 0 reviews	Checked the PCV system and everything is tight and seems to be in its rightful place. The booster line is clamped tight and has no cracks. Maybe the master cylinder? I double checked the timing last night and it won't start at all anymore.i just retarded the timing a hair and boom no spark seems like the coil pack shorted out.