KA24DE Stumbles on idle, dies at lights? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

*MELLO*SOS* · 11-23-2005, 09:40 AM

Okay my (stock + udp) KA24DE stumbles during idle. You can hear it miss every now and again, and the revs are all over the place between 500 and 1000.

Power is good on throttle and decel is normal with occasional popping on throttle lift. But it died about 8 times on the way to work today, every time I was rolling up to a stoplight in neutral.... The revs will drop down from 2000 to 1000 then down to what looks like 200 or so before jumping back up to 800 then down to 200, back and forth until it "stabilizes" with stumble or just dies.

What to check out? I just put in new plugs last night and adjusted the timing. Could this be dirty MAF? Other idea was dirty/sticking IAV?

Any HELPFUL input appreciated, thank you.

aznpoopy · 11-23-2005, 09:47 AM

dirty IACV is most likely

run some throttle body cleaner through the car

or, pull the iacv off and give it a good thorough cleaning

if you want to be super thorough, buy new intake gaskets, pull off the whole intake manifold and clean the whole thing out with a ton of cleaner/degreaser. pull the IACV off the back and clean that out as well. reinstall. you'd be amazed at the difference in feeling. alot of gunk gets in there over the course of 10+ years.

*MELLO*SOS* · 11-23-2005, 09:58 AM

Good idea I will check that out, thanks for the suggestion.

Al_S14 · 11-23-2005, 10:49 AM

i am going to go with messed up MAF. do this. as it idles get a scrw driver and tap on teh maf (with handle) a lot of times if you have faulty maf car will miss really bad and / or die. it does not rull out maf but a lot of times helps narow it down. its also possible you have a hole in your intake piping prior to the MAF. and large amounts of unmetered air will make car stumble

*MELLO*SOS* · 11-23-2005, 11:16 AM

Cool I will check into it, ty!

I know others probably have had this problem??

Ricks15 · 11-24-2005, 01:53 AM

Dude the same exact thing is happening to me but on th KA24E, I was checking my spark plug wires and it seems to be that they are bad and need to be replaced me you need to do the same.

skiboard06 · 11-24-2005, 08:39 AM

anyone know exactly where the iacv is located at or have a picture? thanks

*MELLO*SOS* · 11-28-2005, 09:37 AM

Tapped MAF and checked for leaks, both turned up negative results. I replaced the plugs and took a 420 + 420 = 840 mile drive and the problem is still there...

I am too lazy to look in FSM right now can someone post a pic of where IACV is for me and Skiboard06?

aznpoopy · 11-28-2005, 12:49 PM

the FSM does not have a good picture of the IACV. its this metallic attachment on the back of your intake manifold. it's wedged in there between the manifold and the firewall. i honestly do not know if you can get it off without taking the intake manifold out.

*MELLO*SOS* · 11-28-2005, 04:25 PM

Ahh damn well I have been thinking of ripping the entire manifold off for some time now, maybe this is the excuse I need

Thanks

aznpoopy · 11-28-2005, 04:38 PM

its not bad at all... you need a few good extensions. otherwise its a few vac hoses, a few coolant hoses, the fuel rail, and 15ish bolts. then its out.

as long as you have the whole thing off clean the shiznit out of it, as well as the IACV. you may wnat to consider replacing some of those hard to reach vac hoses. don't forget to buy new gaskets for it when you reinstall. goodluck!

DRFT · 11-28-2005, 08:56 PM

anyone have a good pic of a IACV?

BigVinnie · 11-28-2005, 09:32 PM

Quote:

Originally Posted by aznpoopy

the FSM does not have a good picture of the IACV. its this metallic attachment on the back of your intake manifold. it's wedged in there between the manifold and the firewall. i honestly do not know if you can get it off without taking the intake manifold out.

I have the rough idle at start up too, but it goes away after the engine gets hot.
Screw it I'll check the FSM myself.......

BigVinnie · 11-28-2005, 09:44 PM

In your FSM it is page's 8, and 22 in the EF & EC section.
ENGINE FUEL and EMISSIONS CONTROL, seems like a pretty easy fix!

cdlong · 11-28-2005, 10:32 PM

check for vaccum leaks, my old s13 did the same thing before i fixed it, just a disconnected line under the throttle body.

aznpoopy · 11-29-2005, 06:54 AM

Quote:

Originally Posted by BigVinnie

In your FSM it is page's 8, and 22 in the EF & EC section.
ENGINE FUEL and EMISSIONS CONTROL, seems like a pretty easy fix!

the hardest part really is just pulling it out.

once you have it out spray a ton of throttle body cleaner into it and it'll come out clean. if it was easily accessible it'd definitely be a 2 minute fix.

11-23-2005, 09:40 AM	#1
MELLOSOS* LAID OUT Join Date: Mar 2004 Location: LAS VEGAS Age: 43 Posts: 2,015 Trader Rating: (1) Rides Gallery: MELLO*SOS Feedback Score: 1 reviews	KA24DE Stumbles on idle, dies at lights? Okay my (stock + udp) KA24DE stumbles during idle. You can hear it miss every now and again, and the revs are all over the place between 500 and 1000. Power is good on throttle and decel is normal with occasional popping on throttle lift. But it died about 8 times on the way to work today, every time I was rolling up to a stoplight in neutral.... The revs will drop down from 2000 to 1000 then down to what looks like 200 or so before jumping back up to 800 then down to 200, back and forth until it "stabilizes" with stumble or just dies. What to check out? I just put in new plugs last night and adjusted the timing. Could this be dirty MAF? Other idea was dirty/sticking IAV? Any HELPFUL input appreciated, thank you.

11-28-2005, 09:44 PM	#14
BigVinnie Zilvia FREAK! Join Date: Apr 2003 Location: Walnut Crizzle, Crackifornia Age: 46 Posts: 1,266 Trader Rating: (0) Rides Gallery: BigVinnie Feedback Score: 0 reviews	In your FSM it is page's 8, and 22 in the EF & EC section. ENGINE FUEL and EMISSIONS CONTROL, seems like a pretty easy fix! __________________

11-28-2005, 10:32 PM	#15
cdlong Nissanaholic! Join Date: Jun 2003 Location: Colorado Springs Age: 44 Posts: 1,865 Trader Rating: (0) Rides Gallery: cdlong Feedback Score: 0 reviews	check for vaccum leaks, my old s13 did the same thing before i fixed it, just a disconnected line under the throttle body. __________________

11-23-2005, 09:47 AM	#2
aznpoopy Post Whore! Join Date: Mar 2003 Location: New Jersey Age: 44 Posts: 5,013 Trader Rating: (1) Feedback Score: 1 reviews	dirty IACV is most likely run some throttle body cleaner through the car or, pull the iacv off and give it a good thorough cleaning if you want to be super thorough, buy new intake gaskets, pull off the whole intake manifold and clean the whole thing out with a ton of cleaner/degreaser. pull the IACV off the back and clean that out as well. reinstall. you'd be amazed at the difference in feeling. alot of gunk gets in there over the course of 10+ years.

11-23-2005, 09:58 AM	#3
MELLOSOS* LAID OUT Join Date: Mar 2004 Location: LAS VEGAS Age: 43 Posts: 2,015 Trader Rating: (1) Rides Gallery: MELLO*SOS Feedback Score: 1 reviews	Good idea I will check that out, thanks for the suggestion.

11-23-2005, 10:49 AM	#4
Al_S14 BANNED Join Date: Jan 2005 Location: Chesapeake VA Age: 40 Posts: 405 Trader Rating: (0) Feedback Score: 0 reviews	i am going to go with messed up MAF. do this. as it idles get a scrw driver and tap on teh maf (with handle) a lot of times if you have faulty maf car will miss really bad and / or die. it does not rull out maf but a lot of times helps narow it down. its also possible you have a hole in your intake piping prior to the MAF. and large amounts of unmetered air will make car stumble

11-23-2005, 11:16 AM	#5
MELLOSOS* LAID OUT Join Date: Mar 2004 Location: LAS VEGAS Age: 43 Posts: 2,015 Trader Rating: (1) Rides Gallery: MELLO*SOS Feedback Score: 1 reviews	Cool I will check into it, ty! I know others probably have had this problem??

11-24-2005, 01:53 AM	#6
Ricks15 Nissanaholic! Join Date: Apr 2005 Location: Los Angeles, CA Age: 39 Posts: 1,661 Trader Rating: (1) Feedback Score: 1 reviews	Dude the same exact thing is happening to me but on th KA24E, I was checking my spark plug wires and it seems to be that they are bad and need to be replaced me you need to do the same.

11-24-2005, 08:39 AM	#7
skiboard06 Leaky Injector Join Date: Mar 2005 Location: Cincinnati Posts: 115 Trader Rating: (0) Feedback Score: 0 reviews	anyone know exactly where the iacv is located at or have a picture? thanks

11-28-2005, 09:37 AM	#8
MELLOSOS* LAID OUT Join Date: Mar 2004 Location: LAS VEGAS Age: 43 Posts: 2,015 Trader Rating: (1) Rides Gallery: MELLO*SOS Feedback Score: 1 reviews	Tapped MAF and checked for leaks, both turned up negative results. I replaced the plugs and took a 420 + 420 = 840 mile drive and the problem is still there... I am too lazy to look in FSM right now can someone post a pic of where IACV is for me and Skiboard06?

11-28-2005, 12:49 PM	#9
aznpoopy Post Whore! Join Date: Mar 2003 Location: New Jersey Age: 44 Posts: 5,013 Trader Rating: (1) Feedback Score: 1 reviews	the FSM does not have a good picture of the IACV. its this metallic attachment on the back of your intake manifold. it's wedged in there between the manifold and the firewall. i honestly do not know if you can get it off without taking the intake manifold out.

11-28-2005, 04:25 PM	#10
MELLOSOS* LAID OUT Join Date: Mar 2004 Location: LAS VEGAS Age: 43 Posts: 2,015 Trader Rating: (1) Rides Gallery: MELLO*SOS Feedback Score: 1 reviews	Ahh damn well I have been thinking of ripping the entire manifold off for some time now, maybe this is the excuse I need Thanks

11-28-2005, 04:38 PM	#11
aznpoopy Post Whore! Join Date: Mar 2003 Location: New Jersey Age: 44 Posts: 5,013 Trader Rating: (1) Feedback Score: 1 reviews	its not bad at all... you need a few good extensions. otherwise its a few vac hoses, a few coolant hoses, the fuel rail, and 15ish bolts. then its out. as long as you have the whole thing off clean the shiznit out of it, as well as the IACV. you may wnat to consider replacing some of those hard to reach vac hoses. don't forget to buy new gaskets for it when you reinstall. goodluck!

11-28-2005, 08:56 PM	#12
DRFT Post Whore! Join Date: Apr 2003 Location: Pow Pow Age: 41 Posts: 3,744 Trader Rating: (0) Feedback Score: 0 reviews	anyone have a good pic of a IACV?