Sr20det Terrible Idle. - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Dustxking · 11-25-2012, 05:22 PM

Ive read all of the other posts ive found on here and google, nothing that i have found has helped me, I am sure its something super small that I am not seeing.

S13 sr20det Redtop, powerfc Djet, hks step1 cams,vmount, greddy pulleys, s15 turbo.
Thats the setup. Two weekends ago I was at a local drift event and everything went great! Got the car home, it sat for a week while i was in a busy work week, go out last sunday to try and start the car and drive it around the block, it started. Right after it started it started to idle anywhere from 800-2000 rpm just like a roller coaster, up and down, up and down. I also noticed a smoke coming from under the intake manifold. Took the top half of the intake manifold off and found a cracked house, while it was torn apart i took of the IACV and put a can of carb cleaner through it to see if it was sticking and thats the problem i was having. Nothing if anything i made the idle worse. If i adjust the screw it pretty much does nothing. If i unplug the intake sensor it will idle around 900-1000 pretty well. If i leave the intake sensor plugged in and hold the instake vacuum line closed/half closed it will idle around 900-1000 constant, then almost want to die if i hold it closed.
Here is the weird part, while watching my powerfc, while the car is idleing, my temperature will jump from 15-40 degrees, looks like a slot machine. Once the car is at full operation temp (on the dashboard) the power fc is still looking like a slot machine.

My thoughts are a bad IACV? Would that cause the power fc to go nuts?
Or is it something small I cant find?

Here is a video better showing you what was explained above.

http://www.youtube.com/watch?v=XxuK9...ature=youtu.be

Mikester · 11-26-2012, 07:35 AM

(Can't see vid, I'm at work) First of all, are you sure it's your temp changing drastically, and not the timing? It sounds like normal timing numbers. If it is indeed the temp, you may consider changing the sensor.

Second, did you replace everything with fresh gaskets/hoses when you put it all back together? I assumed the smoke was coolant? If not, you may have a bad turbine.

Dustxking · 11-26-2012, 12:15 PM

^ I fixed the smoke. On the Power fc its saying IGN-temp and its just jumping like crazy. I played with the IACV screw some more and its still idling constant at 2000 RPM.

steve shadows · 11-26-2012, 10:12 PM

What about the throttle body screw? Everyone needs to be reminded that you need to adjust both the throttle body screw as well as the IACV as well as adjusting the Power FC.

Have you synched the Power FC to the CAS?

Also do you have a good or decent map on there?

I'd love to see what the mapping looks like too.

Also the maps they come preloaded with are not kosher for US gas. This is why a lot of people come to me for map service remotely.

Also check the TPS,

Also is the base timing correct, before even beginning the timing synch process (which almost no shops ever remember to do when installing the PFC)...

A few things to think about!

PS. shoot me a PM if you want some direct help to get you going.

Dustxking · 11-27-2012, 08:17 AM

I have had the same map tune on it for the last 3 years. And no I haven't checked the throttle body screw. Will check that out tonight. I'm mostly concerned about the ign temp going nuts on the power FC.

Dustxking · 11-28-2012, 12:42 PM

Update: Ok so after messing with it a few more times, i started the car let it run for 5-10 min, its very very very cold where i am right now so it took a while for it to get warmed up. During warmup the car stayed at 1900 rpm's without bouncing. Once the car cat to 80degrees water temp it then started to go between 1300-2000 rpm and once it started to get warmer then it would start decreasing as in going from 900-1600 and so on and so forth.

smartoss · 11-28-2012, 01:03 PM

It's not 'IGN Temp' it's IGN Timing which is measured in degrees.
The Ignition timing will bounce around like that when the RPMs are bouncing around.

Did you already look over the vacuum lines/ silicone couplers for leaks?

Dustxking · 11-28-2012, 01:22 PM

^ Oh ok thanks for the correction, i did for the most part check almost every vacuum line and couplers. Will probably grab some starting fluid today while im out and check them all again while the car is running.

11-25-2012, 05:22 PM	#1
Dustxking Zilvia Addict Join Date: Nov 2007 Location: 360 Age: 35 Posts: 709 Trader Rating: (4) Feedback Score: 4 reviews	Sr20det Terrible Idle. Ive read all of the other posts ive found on here and google, nothing that i have found has helped me, I am sure its something super small that I am not seeing. S13 sr20det Redtop, powerfc Djet, hks step1 cams,vmount, greddy pulleys, s15 turbo. Thats the setup. Two weekends ago I was at a local drift event and everything went great! Got the car home, it sat for a week while i was in a busy work week, go out last sunday to try and start the car and drive it around the block, it started. Right after it started it started to idle anywhere from 800-2000 rpm just like a roller coaster, up and down, up and down. I also noticed a smoke coming from under the intake manifold. Took the top half of the intake manifold off and found a cracked house, while it was torn apart i took of the IACV and put a can of carb cleaner through it to see if it was sticking and thats the problem i was having. Nothing if anything i made the idle worse. If i adjust the screw it pretty much does nothing. If i unplug the intake sensor it will idle around 900-1000 pretty well. If i leave the intake sensor plugged in and hold the instake vacuum line closed/half closed it will idle around 900-1000 constant, then almost want to die if i hold it closed. Here is the weird part, while watching my powerfc, while the car is idleing, my temperature will jump from 15-40 degrees, looks like a slot machine. Once the car is at full operation temp (on the dashboard) the power fc is still looking like a slot machine. My thoughts are a bad IACV? Would that cause the power fc to go nuts? Or is it something small I cant find? Here is a video better showing you what was explained above. http://www.youtube.com/watch?v=XxuK9...ature=youtu.be

11-26-2012, 07:35 AM	#2
Mikester Nissanaholic! Join Date: Jun 2007 Location: Kathleen, GA Age: 52 Posts: 1,956 Trader Rating: (0) Feedback Score: 0 reviews	(Can't see vid, I'm at work) First of all, are you sure it's your temp changing drastically, and not the timing? It sounds like normal timing numbers. If it is indeed the temp, you may consider changing the sensor. Second, did you replace everything with fresh gaskets/hoses when you put it all back together? I assumed the smoke was coolant? If not, you may have a bad turbine. __________________

11-26-2012, 10:12 PM	#4
steve shadows Post Whore! Join Date: Aug 2003 Location: LA and OC Posts: 8,202 Trader Rating: (5) Feedback Score: 5 reviews	What about the throttle body screw? Everyone needs to be reminded that you need to adjust both the throttle body screw as well as the IACV as well as adjusting the Power FC. Have you synched the Power FC to the CAS? Also do you have a good or decent map on there? I'd love to see what the mapping looks like too. Also the maps they come preloaded with are not kosher for US gas. This is why a lot of people come to me for map service remotely. Also check the TPS, Also is the base timing correct, before even beginning the timing synch process (which almost no shops ever remember to do when installing the PFC)... A few things to think about! PS. shoot me a PM if you want some direct help to get you going. __________________ Like Me on FaceBook !

11-26-2012, 12:15 PM	#3
Dustxking Zilvia Addict Join Date: Nov 2007 Location: 360 Age: 35 Posts: 709 Trader Rating: (4) Feedback Score: 4 reviews	^ I fixed the smoke. On the Power fc its saying IGN-temp and its just jumping like crazy. I played with the IACV screw some more and its still idling constant at 2000 RPM.

11-27-2012, 08:17 AM	#5
Dustxking Zilvia Addict Join Date: Nov 2007 Location: 360 Age: 35 Posts: 709 Trader Rating: (4) Feedback Score: 4 reviews	I have had the same map tune on it for the last 3 years. And no I haven't checked the throttle body screw. Will check that out tonight. I'm mostly concerned about the ign temp going nuts on the power FC.

11-28-2012, 12:42 PM	#6
Dustxking Zilvia Addict Join Date: Nov 2007 Location: 360 Age: 35 Posts: 709 Trader Rating: (4) Feedback Score: 4 reviews	Update: Ok so after messing with it a few more times, i started the car let it run for 5-10 min, its very very very cold where i am right now so it took a while for it to get warmed up. During warmup the car stayed at 1900 rpm's without bouncing. Once the car cat to 80degrees water temp it then started to go between 1300-2000 rpm and once it started to get warmer then it would start decreasing as in going from 900-1600 and so on and so forth.

11-28-2012, 01:03 PM	#7
smartoss Leaky Injector Join Date: Jul 2011 Location: Brainerd MN Age: 37 Posts: 102 Trader Rating: (8) Feedback Score: 8 reviews	It's not 'IGN Temp' it's IGN Timing which is measured in degrees. The Ignition timing will bounce around like that when the RPMs are bouncing around. Did you already look over the vacuum lines/ silicone couplers for leaks?

11-28-2012, 01:22 PM	#8
Dustxking Zilvia Addict Join Date: Nov 2007 Location: 360 Age: 35 Posts: 709 Trader Rating: (4) Feedback Score: 4 reviews	^ Oh ok thanks for the correction, i did for the most part check almost every vacuum line and couplers. Will probably grab some starting fluid today while im out and check them all again while the car is running.