smooth, rough, then smooth idle? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

rv_zenki · 03-10-2015, 12:31 PM

So when i start my car (with a ka24de) it idles fine for 10-20 seconds and then it starts to bounce, low idles for a little bit, then idles normal after a while. Is this a vacuum leak? IACV? TPS? I researched and people just seem to have rough idle but mine goes away after around 5-9 minutes? Any help is appreciated.
Thanks

Kingtal0n · 03-10-2015, 01:49 PM

There are probably 20+ different things to narrow this down.

What I would do:
1. compression test
2. clean IACV
3. clean all accesible plumbing and the maf and air filter
4. tune up, plugs, wires, cap, rotor, pcv valve, fuel filter
5. check wiring / plugs / connections for age/corrosion
6. check battery terminals, ground cables, remove and inspect and re-seat all connections

that should get you started!

what else it could be:
malfunctioning emissions equipment (leaky EGR?)
vacuum leak
failing fuel regulator
aging maf sensor (or filthy maf)
needs a tune up
corrosion on ECU plug

other stuff I posted above

cotbu · 03-10-2015, 02:20 PM

From you description, kinda sounds like the cts.
It does kinda the same thing when too hot or too cold, even though your not technically overheating or over cooled.

Would you be able to get a video with audio of it doing this. You could also pull codes.

From a Highly Tuned Note 4.5!!!

rv_zenki · 03-10-2015, 03:45 PM

Ill get a video of it today, thanks for the advice!

rv_zenki · 03-10-2015, 04:33 PM

https://www.youtube.com/watch?v=OMaxcSn9Xkg heres the video

cotbu · 03-10-2015, 05:17 PM

Im not totally sure now, but you do have a check engine light on so, pull codes and see what up with that.

From a Highly Tuned Note 4.5!!!

rv_zenki · 03-10-2015, 05:29 PM

ive had one ever since this ka went in. yeeeeaaaarrrrs ago. but ill try, thanks

03-10-2015, 12:31 PM	#1
rv_zenki Leaky Injector Join Date: Sep 2013 Location: Kalamazoo, Michigan Posts: 127 Trader Rating: (0) Feedback Score: 0 reviews	smooth, rough, then smooth idle? So when i start my car (with a ka24de) it idles fine for 10-20 seconds and then it starts to bounce, low idles for a little bit, then idles normal after a while. Is this a vacuum leak? IACV? TPS? I researched and people just seem to have rough idle but mine goes away after around 5-9 minutes? Any help is appreciated. Thanks

03-10-2015, 02:20 PM	#3
cotbu Post Whore! Join Date: Sep 2005 Location: SWFL Age: 49 Posts: 3,318 Trader Rating: (3) Feedback Score: 3 reviews	From you description, kinda sounds like the cts. It does kinda the same thing when too hot or too cold, even though your not technically overheating or over cooled. Would you be able to get a video with audio of it doing this. You could also pull codes. From a Highly Tuned Note 4.5!!! __________________ LoverTechnologies "Half Broken Things!"

03-10-2015, 05:17 PM	#6
cotbu Post Whore! Join Date: Sep 2005 Location: SWFL Age: 49 Posts: 3,318 Trader Rating: (3) Feedback Score: 3 reviews	Im not totally sure now, but you do have a check engine light on so, pull codes and see what up with that. From a Highly Tuned Note 4.5!!! __________________ LoverTechnologies "Half Broken Things!"

03-10-2015, 01:49 PM	#2
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 41 Posts: 4,828 Trader Rating: (17) Feedback Score: 17 reviews	There are probably 20+ different things to narrow this down. What I would do: 1. compression test 2. clean IACV 3. clean all accesible plumbing and the maf and air filter 4. tune up, plugs, wires, cap, rotor, pcv valve, fuel filter 5. check wiring / plugs / connections for age/corrosion 6. check battery terminals, ground cables, remove and inspect and re-seat all connections that should get you started! what else it could be: malfunctioning emissions equipment (leaky EGR?) vacuum leak failing fuel regulator aging maf sensor (or filthy maf) needs a tune up corrosion on ECU plug other stuff I posted above

03-10-2015, 03:45 PM	#4
rv_zenki Leaky Injector Join Date: Sep 2013 Location: Kalamazoo, Michigan Posts: 127 Trader Rating: (0) Feedback Score: 0 reviews	Ill get a video of it today, thanks for the advice!

03-10-2015, 04:33 PM	#5
rv_zenki Leaky Injector Join Date: Sep 2013 Location: Kalamazoo, Michigan Posts: 127 Trader Rating: (0) Feedback Score: 0 reviews	https://www.youtube.com/watch?v=OMaxcSn9Xkg heres the video

03-10-2015, 05:29 PM	#7
rv_zenki Leaky Injector Join Date: Sep 2013 Location: Kalamazoo, Michigan Posts: 127 Trader Rating: (0) Feedback Score: 0 reviews	ive had one ever since this ka went in. yeeeeaaaarrrrs ago. but ill try, thanks